Learn C# in One Video

Posted by Derek Banas on Jul 4, 2015 in Web Design | 0 comments

After many requests, finally I finished my learn C# in one video tutorial. I cover a ton in this tutorial including : User input,Data Types, Math, Casting, If, Switch, Ternary Operator, While, Do While, For Loops, Foreach, Strings, Formatting Strings, StringBuilder, Arrays, Lists, Exception Handling, Converting to Data Types, Classes, Objects, Getters, Setters, Constructors, Static, Overloading Methods, Object Initializer, Inheritance, Calling Superclass Methods, Overriding Class Methods, Abstract Classes, Interfaces, Generics, Enums, Structs, Anonymous Methods, Lambda Expressions, File I/O and more. The code follows the video below.

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Code From the Video

// Use using to declare namespaces and functions we wish to use
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using AnimalNS;

/*
Multiline Comment
*/

// Delegates are used to pass methods as arguments to other methods
// A delegate can represent a method with a similar return type and attribute list
delegate double GetSum(double num1, double num2);

// ---------- ENUMS ----------
// Enums are unique types with symbolic names and associated values

public enum Temperature
{
    Freeze,
    Low,
    Warm,
    Boil
}

// ---------- STRUCT ----------
// A struct is a custom type that holds data made up from different data types
struct Customers
{
    private string name;
    private double balance;
    private int id;

    public void createCust(string n, double b, int i)
    {
        name = n;
        balance = b;
        id = i;
    }

    public void showCust()
    {
        Console.WriteLine("Name : " + name);
        Console.WriteLine("Balance : " + balance);
        Console.WriteLine("ID : " + id);
    }
}

// Give our code a custom namespace
namespace ConsoleApplication1
{
    class Program
    {
        // Code in the main function is executed
        static void Main(string[] args)
        {
            // Prints string out to the console with a line break (Write = No Line Break)
            Console.WriteLine("What is your name : ");

            // Accept input from the user
            string name = Console.ReadLine();

            // You can combine Strings with +
            Console.WriteLine("Hello " + name);

            // ---------- DATA TYPES ----------

            // Booleans are true or false
            bool canVote = true;

            // Characters are single 16 bit unicode characters
            char grade = 'A';

            // Integer with a max number of 2,147,483,647
            int maxInt = int.MaxValue;

            // Long with a max number of 9,223,372,036,854,775,807
            long maxLong = long.MaxValue;

            // Decimal has a maximum value of 79,228,162,514,264,337,593,543,950,335
            // If you need something bigger look up BigInteger
            decimal maxDec = decimal.MaxValue;

            // A float is a 32 bit number with a maxValue of 3.402823E+38 with 7 decimals of precision
            float maxFloat = float.MaxValue;

            // A float is a 32 bit number with a maxValue of 1.797693134E+308 with 15 decimals of precision
            double maxDouble = double.MaxValue;

            // You can combine strings with other values with +
            Console.WriteLine("Max Int : " + maxDouble);

            // The dynamic data type is defined at run time 
            dynamic otherName = "Paul";
            otherName = 1;

            // The var data type is defined when compiled and then can't change
            var anotherName = "Tom";
            // ERROR : anotherName = 2;
            Console.WriteLine("Hello " + anotherName);

            // How to get the type and how to format strings
            Console.WriteLine("anotherName is a {0}", anotherName.GetTypeCode());

            // ---------- MATH ----------

            Console.WriteLine("5 + 3 = " + (5 + 3));
            Console.WriteLine("5 - 3 = " + (5 - 3));
            Console.WriteLine("5 * 3 = " + (5 * 3));
            Console.WriteLine("5 / 3 = " + (5 / 3));
            Console.WriteLine("5.2 % 3 = " + (5.2 % 3));

            int i = 0;

            Console.WriteLine("i++ = " + (i++));
            Console.WriteLine("++i = " + (++i));
            Console.WriteLine("i-- = " + (i--));
            Console.WriteLine("--i = " + (--i));

            Console.WriteLine("i += 3 " + (i += 3));
            Console.WriteLine("i -= 2 " + (i -= 2));
            Console.WriteLine("i *= 2 " + (i *= 2));
            Console.WriteLine("i /= 2 " + (i /= 2));
            Console.WriteLine("i %= 2 " + (i %= 2));

            // Casting : If no magnitude is lost casting happens automatically, but otherwise it must be done
            // like this

            double pi = 3.14;
            int intPi = (int)pi; // put the data type to convert to between braces

            // Math Functions
            // Acos, Asin, Atan, Atan2, Cos, Cosh, Exp, Log, Sin, Sinh, Tan, Tanh
            double number1 = 10.5;
            double number2 = 15;

            Console.WriteLine("Math.Abs(number1) " + (Math.Abs(number1)));
            Console.WriteLine("Math.Ceiling(number1) " + (Math.Ceiling(number1)));
            Console.WriteLine("Math.Floor(number1) " + (Math.Floor(number1)));
            Console.WriteLine("Math.Max(number1, number2) " + (Math.Max(number1, number2)));
            Console.WriteLine("Math.Min(number1, number2) " + (Math.Min(number1, number2)));
            Console.WriteLine("Math.Pow(number1, 2) " + (Math.Pow(number1, 2)));
            Console.WriteLine("Math.Round(number1) " + (Math.Round(number1)));
            Console.WriteLine("Math.Sqrt(number1) " + (Math.Sqrt(number1)));

            // Random Numbers
            Random rand = new Random();
            Console.WriteLine("Random Number Between 1 and 10 " + (rand.Next(1,11)));

            // ---------- CONDITIONALS ----------

            // Relational Operators : > < >= <= == !=
            // Logical Operators : && || ^ !

            // If Statement
            int age = 17;

            if ((age >= 5) && (age <= 7)) {
                Console.WriteLine("Go to elementary school");
            }
            else if ((age > 7) && (age < 13)) {
                Console.WriteLine("Go to middle school");
            }
            else {
                Console.WriteLine("Go to high school");
            }

            if ((age < 14) || (age > 67)) {
                Console.WriteLine("You shouldn't work");
            }

            Console.WriteLine("! true = " + (! true));

            // Ternary Operator

            bool canDrive = age >= 16 ? true : false;

            // Switch is used when you have limited options
            // Fall through isn't allowed with C# unless there are no statements between cases
            // You can't check multiple values at once

            switch (age)
            {
                case 0:
                    Console.WriteLine("Infant");
                    break;
                case 1:
                case 2:
                    Console.WriteLine("Toddler");

            // Goto can be used to jump to a label elsewhere in the code
                    goto Cute;
                default:
                    Console.WriteLine("Child");
                    break;
            }

            // Lable we can jump to with Goto
            Cute:
            Console.WriteLine("Toddlers are cute");

            // ---------- LOOPING ----------

            int i = 0;

            while (i < 10)
            {
                // If i = 7 then skip the rest of the code and start with i = 8
                if (i == 7)
                {
                    i++;
                    continue; 
                }

                // Jump completely out of the loop if i = 9
                if (i == 9)
                {
                    break;
                }

                // You can't convert an int into a bool : Print out only odds
                if ((i % 2) > 0)
                {
                    Console.WriteLine(i);
                }
                i++;
            }

            // The do while loop will go through the loop at least once
            string guess;
            do
            {
                Console.WriteLine("Guess a Number ");
                guess = Console.ReadLine();
            } while (! guess.Equals("15")); // How to check String equality

            // Puts all changes to the iterator in one place
            for(int j = 0; j < 10; j++)
            {
                if ((j % 2) > 0)
                {
                    Console.WriteLine(j);
                }
            }

            // foreach cycles through every item in an array or collection
            string randStr = "Here are some random characters";

            foreach( char c in randStr)
            {
                Console.WriteLine(c);
            }

            // ---------- STRINGS ----------

            // Escape Sequences : \' \" \\ \b \n \t

            string sampString = "A bunch of random words";

            // Check if empty
            Console.WriteLine("Is empty " + String.IsNullOrEmpty(sampString));
            Console.WriteLine("Is empty " + String.IsNullOrWhiteSpace(sampString));
            Console.WriteLine("String Length " + sampString.Length);

            // Find a string index (Starts with 0)
            Console.WriteLine("Index of bunch " + sampString.IndexOf("bunch"));

            // Get a substring
            Console.WriteLine("2nd Word " + sampString.Substring(2, 6));

            string sampString2 = "More random words";

            // Are strings equal
            Console.WriteLine("Strings equal " + sampString.Equals(sampString2));

            // Compare strings
            Console.WriteLine("Starts with A bunch " + sampString.StartsWith("A bunch"));
            Console.WriteLine("Ends with words " + sampString.EndsWith("words"));

            // Trim white space at beginning and end or (TrimEnd / TrimStart)
            sampString = sampString.Trim();

            // Replace words or characters
            sampString = sampString.Replace("words", "characters");
            Console.WriteLine(sampString);

            // Remove starting at a defined index up to the second index
            sampString = sampString.Remove(0,2);
            Console.WriteLine(sampString);

            // Join values in array and save to string
            string[] names = new string[3] { "Matt", "Joe", "Paul" };
            Console.WriteLine("Name List " + String.Join(", ", names));

            // Formatting : Currency, Decimal Places, Before Decimals, Thousands Separator
            string fmtStr = String.Format("{0:c} {1:00.00} {2:#.00} {3:0,0}", 1.56, 15.567, .56, 1000);

            Console.WriteLine(fmtStr.ToString());

            // ---------- STRINGBUILDER ----------
            // Each time you create a string you actually create another string in memory
            // StringBuilders are used when you want to be able to edit a string without creating new ones

            StringBuilder sb = new StringBuilder();

            // Append a string to the StringBuilder (AppendLine also adds a newline at the end)
            sb.Append("This is the first sentence.");

            // Append a formatted string
            sb.AppendFormat("My name is {0} and I live in {1}", "Derek", "Pennsylvania");

            // Clear the StringBuilder
            // sb.Clear();

            // Replaces every instance of the first with the second
            sb.Replace("a", "e");

            // Remove characters starting at the index and then up to the defined index
            sb.Remove(5, 7);

            // Out put everything
            Console.WriteLine(sb.ToString());

            // ---------- ARRAYS ----------
            // Declare an array
            int[] randNumArray;

            // Declare the number of items an array can contain
            int[] randArray = new int[5];

            // Declare and initialize an array
            int[] randArray2 = { 1, 2, 3, 4, 5 };

            // Get array length
            Console.WriteLine("Array Length " + randArray2.Length);

            // Get item at index
            Console.WriteLine("Item 0 " + randArray2[0]);

            // Cycle through array
            for (int i = 0; i < randArray2.Length; i++)
            {
                Console.WriteLine("{0} : {1}", i, randArray2[i]);
            }

            // Cycle with foreach
            foreach (int num in randArray2)
            {
                Console.WriteLine(num);
            }

            // Get the index of an item or -1
            Console.WriteLine("Where is 1 " + Array.IndexOf(randArray2, 1));

            string[] names = { "Tom", "Paul", "Sally" };

            // Join an array into a string
            string nameStr = string.Join(", ", names);
            Console.WriteLine(nameStr);

            // Split a string into an array
            string[] nameArray = nameStr.Split(',');

            // Create a multidimensional array
            int[,] multArray = new int[5, 3];

            // Create and initialize a multidimensional array
            int[,] multArray2 = { { 0, 1 }, { 2, 3 }, { 4, 5 } };

            // Cycle through multidimensional array
            foreach(int num in multArray2)
            {
                Console.WriteLine(num);
            }

            // Cycle and have access to indexes
            for (int x = 0; x < multArray2.GetLength(0); x += 1)
            {
                for (int y = 0; y < multArray2.GetLength(1); y += 1)
                {
                    Console.WriteLine("{0} | {1} : {2}", x, y, multArray2[x, y]);
                }
            }

            // ---------- LISTS ----------
            // A list unlike an array automatically resizes

            // Create a list and add values
            List<int> numList = new List<int>();
            numList.Add(5);
            numList.Add(15);
            numList.Add(25);

            // Add an array to a list
            int[] randArray = { 1, 2, 3, 4, 5 };
            numList.AddRange(randArray);

            // Clear a list
            // numList.Clear();

            // Copy an array into a List
            List<int> numList2 = new List<int>(randArray);

            // Create a List with array
            List<int> numList3 = new List<int>(new int[] { 1, 2, 3, 4 });

            // Insert in a specific index
            numList.Insert(1, 10);

            // Remove a specific value
            numList.Remove(5);

            // Remove at an index
            numList.RemoveAt(2);

            // Cycle through a List with foreach or
            for (int i = 0; i < numList.Count; i++)
            {
                Console.WriteLine(numList[i]);
            }

            // Return the index for a value or -1
            Console.WriteLine("4 is in index " + numList3.IndexOf(4));

            // Does the List contain a value
            Console.WriteLine("5 in list " + numList3.Contains(5));

            // Search for a value in a string List
            List<string> strList = new List<string>(new string[] { "Tom","Paul" });
            Console.WriteLine("Tom in list " + strList.Contains("tom", StringComparer.OrdinalIgnoreCase));

            // Sort the List
            strList.Sort();

            // ---------- EXCEPTION HANDLING ----------
            // All the exceptions 
            // msdn.microsoft.com/en-us/library/system.systemexception.aspx#inheritanceContinued

                try
                {
                    Console.Write("Divide 10 by ");
                    int num = int.Parse(Console.ReadLine());
                    Console.WriteLine("10 / {0} =  {1}", num, (10/num));

                }

                // Specifically catches the divide by zero exception
                catch (DivideByZeroException ex)
                {
                    Console.WriteLine("Can't divide by zero");

                    // Get additonal info on the exception
                    Console.WriteLine(ex.GetType().Name);
                    Console.WriteLine(ex.Message);

                    // Throw the exception to the next inline
                    // throw ex;

                    // Throw a specific exception
                    throw new InvalidOperationException("Operation Failed", ex);
                }

                // Catches any other exception
                catch (Exception ex)
                {
                    Console.WriteLine("An error occurred");
                    Console.WriteLine(ex.GetType().Name);
                    Console.WriteLine(ex.Message);
                }

            // ---------- CLASSES & OBJECTS ----------

            Animal bulldog = new Animal(13, 50, "Spot", "Woof");

            Console.WriteLine("{0} says {1}", bulldog.name, bulldog.sound);

            // Console.WriteLine("No. of Animals " + Animal.getNumOfAnimals());

            // ---------- ENUMS ----------

            Temperature micTemp = Temperature.Low;
            Console.Write("What Temp : ");

            Console.ReadLine();

            switch (micTemp)
            {
                case Temperature.Freeze:
                    Console.WriteLine("Temp on Freezing");
                    break;

                case Temperature.Low:
                    Console.WriteLine("Temp on Low");
                    break;

                case Temperature.Warm:
                    Console.WriteLine("Temp on Warm");
                    break;

                case Temperature.Boil:
                    Console.WriteLine("Temp on Boil");
                    break;
            }

            // ---------- STRUCTS ----------
            Customers bob = new Customers();

            bob.createCust("Bob", 15.50, 12345);

            bob.showCust();

            // ---------- ANONYMOUS METHODS ----------
            // An anonymous method has no name and its return type is defined by the return used in the method

            GetSum sum = delegate (double num1, double num2) {
                return num1 + num2;
            };

            Console.WriteLine("5 + 10 = " + sum(5, 10));

            // ---------- LAMBDA EXPRESSIONS ----------
            // A lambda expression is used to act as an anonymous function or expression tree

            // You can assign the lambda expression to a function instance
            Func<int, int, int> getSum = (x, y) => x + y;
            Console.WriteLine("5 + 3 = " + getSum.Invoke(5, 3));

            // Get odd numbers from a list
            List<int> numList = new List<int> { 5, 10, 15, 20, 25 };

            // With an Expression Lambda the input goes in the left (n) and the statements go on the right
            List<int> oddNums = numList.Where(n => n % 2 == 1).ToList();

            foreach (int num in oddNums) {
                Console.Write(num + ", ");
            }

            // ---------- FILE I/O ----------
            // The StreamReader and StreamWriter allows you to create text files while reading and 
            // writing to them

            string[] custs = new string[] { "Tom", "Paul", "Greg" };

            using (StreamWriter sw = new StreamWriter("custs.txt"))
            {
                foreach(string cust in custs)
                {
                    sw.WriteLine(cust);
                }
            }

            string custName = "";
            using (StreamReader sr = new StreamReader("custs.txt"))
            {
                while ((custName = sr.ReadLine()) != null)
                {
                    Console.WriteLine(custName);
                }
            }

            Console.Write("Hit Enter to Exit");
            string exitApp = Console.ReadLine();

        }
    }
}

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// Use using to declare namespaces and functions we wish to use

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using AnimalNS;

Multiline Comment

// Delegates are used to pass methods as arguments to other methods

// A delegate can represent a method with a similar return type and attribute list

delegate double GetSum(double num1, double num2);

// ---------- ENUMS ----------

// Enums are unique types with symbolic names and associated values

public enum Temperature

{

Freeze,

Low,

Warm,

Boil

}

// ---------- STRUCT ----------

// A struct is a custom type that holds data made up from different data types

struct Customers

{

private string name;

private double balance;

private int id;

public void createCust(string n, double b, int i)

{

name = n;

balance = b;

id = i;

}

public void showCust()

{

Console.WriteLine("Name : " + name);

Console.WriteLine("Balance : " + balance);

Console.WriteLine("ID : " + id);

}

// Give our code a custom namespace

namespace ConsoleApplication1

{

class Program

{

// Code in the main function is executed

static void Main(string[] args)

{

// Prints string out to the console with a line break (Write = No Line Break)

Console.WriteLine("What is your name : ");

// Accept input from the user

string name = Console.ReadLine();

// You can combine Strings with +

Console.WriteLine("Hello " + name);

// ---------- DATA TYPES ----------

// Booleans are true or false

bool canVote = true;

// Characters are single 16 bit unicode characters

char grade = 'A';

// Integer with a max number of 2,147,483,647

int maxInt = int.MaxValue;

// Long with a max number of 9,223,372,036,854,775,807

long maxLong = long.MaxValue;

// Decimal has a maximum value of 79,228,162,514,264,337,593,543,950,335

// If you need something bigger look up BigInteger

decimal maxDec = decimal.MaxValue;

// A float is a 32 bit number with a maxValue of 3.402823E+38 with 7 decimals of precision

float maxFloat = float.MaxValue;

// A float is a 32 bit number with a maxValue of 1.797693134E+308 with 15 decimals of precision

double maxDouble = double.MaxValue;

// You can combine strings with other values with +

Console.WriteLine("Max Int : " + maxDouble);

// The dynamic data type is defined at run time

dynamic otherName = "Paul";

otherName = 1;

// The var data type is defined when compiled and then can't change

var anotherName = "Tom";

// ERROR : anotherName = 2;

Console.WriteLine("Hello " + anotherName);

// How to get the type and how to format strings

Console.WriteLine("anotherName is a {0}", anotherName.GetTypeCode());

// ---------- MATH ----------

Console.WriteLine("5 + 3 = " + (5 + 3));

Console.WriteLine("5 - 3 = " + (5 - 3));

Console.WriteLine("5 * 3 = " + (5 * 3));

Console.WriteLine("5 / 3 = " + (5 / 3));

Console.WriteLine("5.2 % 3 = " + (5.2 % 3));

int i = 0;

Console.WriteLine("i++ = " + (i++));

Console.WriteLine("++i = " + (++i));

Console.WriteLine("i-- = " + (i--));

Console.WriteLine("--i = " + (--i));

Console.WriteLine("i += 3 " + (i += 3));

Console.WriteLine("i -= 2 " + (i -= 2));

Console.WriteLine("i *= 2 " + (i *= 2));

Console.WriteLine("i /= 2 " + (i /= 2));

Console.WriteLine("i %= 2 " + (i %= 2));

// Casting : If no magnitude is lost casting happens automatically, but otherwise it must be done

// like this

double pi = 3.14;

int intPi = (int)pi; // put the data type to convert to between braces

// Math Functions

// Acos, Asin, Atan, Atan2, Cos, Cosh, Exp, Log, Sin, Sinh, Tan, Tanh

double number1 = 10.5;

double number2 = 15;

Console.WriteLine("Math.Abs(number1) " + (Math.Abs(number1)));

Console.WriteLine("Math.Ceiling(number1) " + (Math.Ceiling(number1)));

Console.WriteLine("Math.Floor(number1) " + (Math.Floor(number1)));

Console.WriteLine("Math.Max(number1, number2) " + (Math.Max(number1, number2)));

Console.WriteLine("Math.Min(number1, number2) " + (Math.Min(number1, number2)));

Console.WriteLine("Math.Pow(number1, 2) " + (Math.Pow(number1, 2)));

Console.WriteLine("Math.Round(number1) " + (Math.Round(number1)));

Console.WriteLine("Math.Sqrt(number1) " + (Math.Sqrt(number1)));

// Random Numbers

Random rand = new Random();

Console.WriteLine("Random Number Between 1 and 10 " + (rand.Next(1,11)));

// ---------- CONDITIONALS ----------

// Relational Operators : > < >= <= == !=

// Logical Operators : && || ^ !

// If Statement

int age = 17;

if ((age >= 5) && (age <= 7)) {

Console.WriteLine("Go to elementary school");

}

else if ((age > 7) && (age < 13)) {

Console.WriteLine("Go to middle school");

}

else {

Console.WriteLine("Go to high school");

}

if ((age < 14) || (age > 67)) {

Console.WriteLine("You shouldn't work");

}

Console.WriteLine("! true = " + (! true));

// Ternary Operator

bool canDrive = age >= 16 ? true : false;

// Switch is used when you have limited options

// Fall through isn't allowed with C# unless there are no statements between cases

// You can't check multiple values at once

switch (age)

{

case 0:

Console.WriteLine("Infant");

break;

case 1:

case 2:

Console.WriteLine("Toddler");

// Goto can be used to jump to a label elsewhere in the code

goto Cute;

default:

Console.WriteLine("Child");

break;

}

// Lable we can jump to with Goto

Cute:

Console.WriteLine("Toddlers are cute");

// ---------- LOOPING ----------

int i = 0;

while (i < 10)

{

// If i = 7 then skip the rest of the code and start with i = 8

if (i == 7)

{

i++;

continue;

}

// Jump completely out of the loop if i = 9

if (i == 9)

{

break;

}

// You can't convert an int into a bool : Print out only odds

if ((i % 2) > 0)

{

Console.WriteLine(i);

}

i++;

}

// The do while loop will go through the loop at least once

string guess;

{

Console.WriteLine("Guess a Number ");

guess = Console.ReadLine();

} while (! guess.Equals("15")); // How to check String equality

// Puts all changes to the iterator in one place

for(int j = 0; j < 10; j++)

{

if ((j % 2) > 0)

{

Console.WriteLine(j);

}

// foreach cycles through every item in an array or collection

string randStr = "Here are some random characters";

foreach( char c in randStr)

{

Console.WriteLine(c);

}

// ---------- STRINGS ----------

// Escape Sequences : \' \" \\ \b \n \t

string sampString = "A bunch of random words";

// Check if empty

Console.WriteLine("Is empty " + String.IsNullOrEmpty(sampString));

Console.WriteLine("Is empty " + String.IsNullOrWhiteSpace(sampString));

Console.WriteLine("String Length " + sampString.Length);

// Find a string index (Starts with 0)

Console.WriteLine("Index of bunch " + sampString.IndexOf("bunch"));

// Get a substring

Console.WriteLine("2nd Word " + sampString.Substring(2, 6));

string sampString2 = "More random words";

// Are strings equal

Console.WriteLine("Strings equal " + sampString.Equals(sampString2));

// Compare strings

Console.WriteLine("Starts with A bunch " + sampString.StartsWith("A bunch"));

Console.WriteLine("Ends with words " + sampString.EndsWith("words"));

// Trim white space at beginning and end or (TrimEnd / TrimStart)

sampString = sampString.Trim();

// Replace words or characters

sampString = sampString.Replace("words", "characters");

Console.WriteLine(sampString);

// Remove starting at a defined index up to the second index

sampString = sampString.Remove(0,2);

Console.WriteLine(sampString);

// Join values in array and save to string

string[] names = new string[3] { "Matt", "Joe", "Paul" };

Console.WriteLine("Name List " + String.Join(", ", names));

// Formatting : Currency, Decimal Places, Before Decimals, Thousands Separator

string fmtStr = String.Format("{0:c} {1:00.00} {2:#.00} {3:0,0}", 1.56, 15.567, .56, 1000);

Console.WriteLine(fmtStr.ToString());

// ---------- STRINGBUILDER ----------

// Each time you create a string you actually create another string in memory

// StringBuilders are used when you want to be able to edit a string without creating new ones

StringBuilder sb = new StringBuilder();

// Append a string to the StringBuilder (AppendLine also adds a newline at the end)

sb.Append("This is the first sentence.");

// Append a formatted string

sb.AppendFormat("My name is {0} and I live in {1}", "Derek", "Pennsylvania");

// Clear the StringBuilder

// sb.Clear();

// Replaces every instance of the first with the second

sb.Replace("a", "e");

// Remove characters starting at the index and then up to the defined index

sb.Remove(5, 7);

// Out put everything

Console.WriteLine(sb.ToString());

// ---------- ARRAYS ----------

// Declare an array

int[] randNumArray;

// Declare the number of items an array can contain

int[] randArray = new int[5];

// Declare and initialize an array

int[] randArray2 = { 1, 2, 3, 4, 5 };

// Get array length

Console.WriteLine("Array Length " + randArray2.Length);

// Get item at index

Console.WriteLine("Item 0 " + randArray2[0]);

// Cycle through array

for (int i = 0; i < randArray2.Length; i++)

{

Console.WriteLine("{0} : {1}", i, randArray2[i]);

}

// Cycle with foreach

foreach (int num in randArray2)

{

Console.WriteLine(num);

}

// Get the index of an item or -1

Console.WriteLine("Where is 1 " + Array.IndexOf(randArray2, 1));

string[] names = { "Tom", "Paul", "Sally" };

// Join an array into a string

string nameStr = string.Join(", ", names);

Console.WriteLine(nameStr);

// Split a string into an array

string[] nameArray = nameStr.Split(',');

// Create a multidimensional array

int[,] multArray = new int[5, 3];

// Create and initialize a multidimensional array

int[,] multArray2 = { { 0, 1 }, { 2, 3 }, { 4, 5 } };

// Cycle through multidimensional array

foreach(int num in multArray2)

{

Console.WriteLine(num);

}

// Cycle and have access to indexes

for (int x = 0; x < multArray2.GetLength(0); x += 1)

{

for (int y = 0; y < multArray2.GetLength(1); y += 1)

{

Console.WriteLine("{0} | {1} : {2}", x, y, multArray2[x, y]);

}

// ---------- LISTS ----------

// A list unlike an array automatically resizes

// Create a list and add values

List<int> numList = new List<int>();

numList.Add(5);

numList.Add(15);

numList.Add(25);

// Add an array to a list

int[] randArray = { 1, 2, 3, 4, 5 };

numList.AddRange(randArray);

// Clear a list

// numList.Clear();

// Copy an array into a List

List<int> numList2 = new List<int>(randArray);

// Create a List with array

List<int> numList3 = new List<int>(new int[] { 1, 2, 3, 4 });

// Insert in a specific index

numList.Insert(1, 10);

// Remove a specific value

numList.Remove(5);

// Remove at an index

numList.RemoveAt(2);

// Cycle through a List with foreach or

for (int i = 0; i < numList.Count; i++)

{

Console.WriteLine(numList[i]);

}

// Return the index for a value or -1

Console.WriteLine("4 is in index " + numList3.IndexOf(4));

// Does the List contain a value

Console.WriteLine("5 in list " + numList3.Contains(5));

// Search for a value in a string List

List<string> strList = new List<string>(new string[] { "Tom","Paul" });

Console.WriteLine("Tom in list " + strList.Contains("tom", StringComparer.OrdinalIgnoreCase));

// Sort the List

strList.Sort();

// ---------- EXCEPTION HANDLING ----------

// All the exceptions

// msdn.microsoft.com/en-us/library/system.systemexception.aspx#inheritanceContinued

try

{

Console.Write("Divide 10 by ");

int num = int.Parse(Console.ReadLine());

Console.WriteLine("10 / {0} = {1}", num, (10/num));

}

// Specifically catches the divide by zero exception

catch (DivideByZeroException ex)

{

Console.WriteLine("Can't divide by zero");

// Get additonal info on the exception

Console.WriteLine(ex.GetType().Name);

Console.WriteLine(ex.Message);

// Throw the exception to the next inline

// throw ex;

// Throw a specific exception

throw new InvalidOperationException("Operation Failed", ex);

}

// Catches any other exception

catch (Exception ex)

{

Console.WriteLine("An error occurred");

Console.WriteLine(ex.GetType().Name);

Console.WriteLine(ex.Message);

}

// ---------- CLASSES & OBJECTS ----------

Animal bulldog = new Animal(13, 50, "Spot", "Woof");

Console.WriteLine("{0} says {1}", bulldog.name, bulldog.sound);

// Console.WriteLine("No. of Animals " + Animal.getNumOfAnimals());

// ---------- ENUMS ----------

Temperature micTemp = Temperature.Low;

Console.Write("What Temp : ");

Console.ReadLine();

switch (micTemp)

{

case Temperature.Freeze:

Console.WriteLine("Temp on Freezing");

break;

case Temperature.Low:

Console.WriteLine("Temp on Low");

break;

case Temperature.Warm:

Console.WriteLine("Temp on Warm");

break;

case Temperature.Boil:

Console.WriteLine("Temp on Boil");

break;

}

// ---------- STRUCTS ----------

Customers bob = new Customers();

bob.createCust("Bob", 15.50, 12345);

bob.showCust();

// ---------- ANONYMOUS METHODS ----------

// An anonymous method has no name and its return type is defined by the return used in the method

GetSum sum = delegate (double num1, double num2) {

return num1 + num2;

};

Console.WriteLine("5 + 10 = " + sum(5, 10));

// ---------- LAMBDA EXPRESSIONS ----------

// A lambda expression is used to act as an anonymous function or expression tree

// You can assign the lambda expression to a function instance

Func<int, int, int> getSum = (x, y) => x + y;

Console.WriteLine("5 + 3 = " + getSum.Invoke(5, 3));

// Get odd numbers from a list

List<int> numList = new List<int> { 5, 10, 15, 20, 25 };

// With an Expression Lambda the input goes in the left (n) and the statements go on the right

List<int> oddNums = numList.Where(n => n % 2 == 1).ToList();

foreach (int num in oddNums) {

Console.Write(num + ", ");

}

// ---------- FILE I/O ----------

// The StreamReader and StreamWriter allows you to create text files while reading and

// writing to them

string[] custs = new string[] { "Tom", "Paul", "Greg" };

using (StreamWriter sw = new StreamWriter("custs.txt"))

{

foreach(string cust in custs)

{

sw.WriteLine(cust);

}

string custName = "";

using (StreamReader sr = new StreamReader("custs.txt"))

{

while ((custName = sr.ReadLine()) != null)

{

Console.WriteLine(custName);

}

Console.Write("Hit Enter to Exit");

string exitApp = Console.ReadLine();

}

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication2
{
    class Animal
    {

        // public : Access is not limited
        // protected : Access is limited to the class methods and subclasses
        // private : Access is limited to only this classes methods
        public double height { get; set; }
        public double weight { get; set; }
        public string sound { get; set; }

        // We can either have C# create the getters and setters or create them ourselves to verify data
        public string name;
        public string Name
        {
            get { return name; }
            set { name = value; }
        }

        // Every object has a default constructor that receives no attributes
        // The constructor initializes every object created
        // this is used to refer to this objects specific fields since we don't know the objects given name

        // The default constructor isn't created if you create any other constructor
        public Animal()
        {
            this.height = 0;
            this.weight = 0;
            this.name = "No Name";
            this.sound = "No Sound";

            numOfAnimals++;
        }

        // You can create custom constructors as well
        public Animal(double height, double weight, string name, string sound)
        {
            this.height = height;
            this.weight = weight;
            this.name = name;
            this.sound = sound;

            numOfAnimals++;
        }

        // A static fields value is shared by every object of the Animal class
        // We declare thinsg static when it doesn't make sense for our object to either have the property or
        // the capability to do something (Animals can't count)
        static int numOfAnimals = 0;

        // A static method cannot access non-static class members
        public static int getNumOfAnimals()
        {
            return numOfAnimals;
        }

        // Declare a method
        public string toString()
        {
            return String.Format("{0} is {1} inches tall, weighs {2} lbs and likes to say {3}", name, height, weight, sound);
        }

        // Overloading methods works if you have methods with different attribute data types
        // You can give attributes default values
        public int getSum(int num1 = 1, int num2 = 1)
        {
            return num1 + num2;
        }

        public double getSum(double num1, double num2)
        {
            return num1 + num2;
        }

        static void Main(string[] args)
        {
            // Create an Animal object and call the constructor
            Animal spot = new Animal(15, 10, "Spot", "Woof");

            // Get object values with the dot operator
            Console.WriteLine("{0} says {1}", spot.name, spot.sound);

            // Calling a static method
            Console.WriteLine("Number of Animals " + Animal.getNumOfAnimals());

            // Calling an object method
            Console.WriteLine(spot.toString());

            Console.WriteLine("3 + 4 = " + spot.getSum(3, 4));

            // You can assign attributes by name
            Console.WriteLine("3.4 + 4.5 = " + spot.getSum(num2: 3.4, num1: 4.5));

            // You can create objects with an object initializer
            Animal grover = new Animal
            {
                name = "Grover",
                height = 16,
                weight = 18,
                sound = "Grrr"
            };

            Console.WriteLine(grover.toString());

            // Create a subclass Dog object
            Dog spike = new Dog();

            Console.WriteLine(spike.toString());

            spike = new Dog(20, 15, "Spike", "Grrr Woof", "Chicken");

            Console.WriteLine(spike.toString());

            // One way to implement polymorphism is through an abstract class
            Shape rect = new Rectangle(5, 5);
            Shape tri = new Triangle(5, 5);
            Console.WriteLine("Rect Area " + rect.area());
            Console.WriteLine("Trit Area " + tri.area());

            // Using the overloaded + on 2 Rectangles
            Rectangle combRect = new Rectangle(5, 5) + new Rectangle(5, 5);

            Console.WriteLine("combRect Area = " + combRect.area());

            // ---------- GENERICS ----------
            // With Generics you don't have to specify the data type of an element in a class or method
            KeyValue<string, string> superman = new KeyValue<string, string>("","");
            superman.key = "Superman";
            superman.value = "Clark Kent";
            superman.showData();

            // Now use completely different types
            KeyValue<int, string> samsungTV = new KeyValue<int, string>(0, "");
            samsungTV.key = 123456;
            samsungTV.value = "a 50in Samsung TV";
            samsungTV.showData();

            Console.Write("Hit Enter to Exit");
            string exitApp = Console.ReadLine();

        }
    }

    class Dog : Animal
    {
        public string favFood { get; set; }

        // Set the favFood default and then call the Animal super class constructor
        public Dog() : base()
        {
            this.favFood = "No Favorite Food";
        }

        public Dog(double height, double weight, string name, string sound, string favFood) :
            base(height, weight, name, sound)
        {
            this.favFood = favFood;
        }

        // Override methods with the keyword new
        new public string toString()
        {
            return String.Format("{0} is {1} inches tall, weighs {2} lbs, likes to say {3} and eats {4}", name, height, weight, sound, favFood);
        }

    }

    // Abstract classes define methods that must be defined by derived classes
    // You can only inherit one abstract class per class
    // You can't instantiate an abstract class
    abstract class Shape
    {
        public abstract double area();

        // An abstract class can contain complete or default code for methods
        public void sayHi()
        {
            Console.WriteLine("Hello");
        }
    }

    // A class can have many interfaces
    // An interface can't have concrete code
    public interface ShapeItem
    {
        double area();
    }

    class Rectangle : Shape
    {
        private double length;
        private double width;

        public Rectangle( double num1, double num2)
        {
            length = num1;
            width = num2;
        }

        public override double area()
        {
            return length * width;
        }

        // You can redefine many built in operators so that you can define what happens when you 
        // add to Rectangles
        public static Rectangle operator+ (Rectangle rect1, Rectangle rect2)
        {
            double rectLength = rect1.length + rect2.length;
            double rectWidth = rect1.width + rect2.width;

            return new Rectangle(rectLength, rectWidth);

        }

    }

    class Triangle : Shape
    {
        private double theBase;
        private double height;

        public Triangle(double num1, double num2)
        {
            theBase = num1;
            height = num2;
        }

        public override double area()
        {
            return .5 * (theBase * height);
        }
    }

    // ---------- GENERIC CLASS ----------

    class KeyValue<TKey, TValue>
    {
        public TKey key { get; set; }
        public TValue value { get; set; }

        public KeyValue(TKey k, TValue v)
        {
            key = k;
            value = v;
        }

        public void showData()
        {
            Console.WriteLine("{0} is {1}", this.key, this.value);
        }

    }

}

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using System;

using System.Collections.Generic;

using System.IO;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace ConsoleApplication2

{

class Animal

{

// public : Access is not limited

// protected : Access is limited to the class methods and subclasses

// private : Access is limited to only this classes methods

public double height { get; set; }

public double weight { get; set; }

public string sound { get; set; }

// We can either have C# create the getters and setters or create them ourselves to verify data

public string name;

public string Name

{

get { return name; }

set { name = value; }

}

// Every object has a default constructor that receives no attributes

// The constructor initializes every object created

// this is used to refer to this objects specific fields since we don't know the objects given name

// The default constructor isn't created if you create any other constructor

public Animal()

{

this.height = 0;

this.weight = 0;

this.name = "No Name";

this.sound = "No Sound";

numOfAnimals++;

}

// You can create custom constructors as well

public Animal(double height, double weight, string name, string sound)

{

this.height = height;

this.weight = weight;

this.name = name;

this.sound = sound;

numOfAnimals++;

}

// A static fields value is shared by every object of the Animal class

// We declare thinsg static when it doesn't make sense for our object to either have the property or

// the capability to do something (Animals can't count)

static int numOfAnimals = 0;

// A static method cannot access non-static class members

public static int getNumOfAnimals()

{

return numOfAnimals;

}

// Declare a method

public string toString()

{

return String.Format("{0} is {1} inches tall, weighs {2} lbs and likes to say {3}", name, height, weight, sound);

}

// Overloading methods works if you have methods with different attribute data types

// You can give attributes default values

public int getSum(int num1 = 1, int num2 = 1)

{

return num1 + num2;

}

public double getSum(double num1, double num2)

{

return num1 + num2;

}

static void Main(string[] args)

{

// Create an Animal object and call the constructor

Animal spot = new Animal(15, 10, "Spot", "Woof");

// Get object values with the dot operator

Console.WriteLine("{0} says {1}", spot.name, spot.sound);

// Calling a static method

Console.WriteLine("Number of Animals " + Animal.getNumOfAnimals());

// Calling an object method

Console.WriteLine(spot.toString());

Console.WriteLine("3 + 4 = " + spot.getSum(3, 4));

// You can assign attributes by name

Console.WriteLine("3.4 + 4.5 = " + spot.getSum(num2: 3.4, num1: 4.5));

// You can create objects with an object initializer

Animal grover = new Animal

{

name = "Grover",

height = 16,

weight = 18,

sound = "Grrr"

};

Console.WriteLine(grover.toString());

// Create a subclass Dog object

Dog spike = new Dog();

Console.WriteLine(spike.toString());

spike = new Dog(20, 15, "Spike", "Grrr Woof", "Chicken");

Console.WriteLine(spike.toString());

// One way to implement polymorphism is through an abstract class

Shape rect = new Rectangle(5, 5);

Shape tri = new Triangle(5, 5);

Console.WriteLine("Rect Area " + rect.area());

Console.WriteLine("Trit Area " + tri.area());

// Using the overloaded + on 2 Rectangles

Rectangle combRect = new Rectangle(5, 5) + new Rectangle(5, 5);

Console.WriteLine("combRect Area = " + combRect.area());

// ---------- GENERICS ----------

// With Generics you don't have to specify the data type of an element in a class or method

KeyValue<string, string> superman = new KeyValue<string, string>("","");

superman.key = "Superman";

superman.value = "Clark Kent";

superman.showData();

// Now use completely different types

KeyValue<int, string> samsungTV = new KeyValue<int, string>(0, "");

samsungTV.key = 123456;

samsungTV.value = "a 50in Samsung TV";

samsungTV.showData();

Console.Write("Hit Enter to Exit");

string exitApp = Console.ReadLine();

}

class Dog : Animal

{

public string favFood { get; set; }

// Set the favFood default and then call the Animal super class constructor

public Dog() : base()

{

this.favFood = "No Favorite Food";

}

public Dog(double height, double weight, string name, string sound, string favFood) :

base(height, weight, name, sound)

{

this.favFood = favFood;

}

// Override methods with the keyword new

new public string toString()

{

return String.Format("{0} is {1} inches tall, weighs {2} lbs, likes to say {3} and eats {4}", name, height, weight, sound, favFood);

}

// Abstract classes define methods that must be defined by derived classes

// You can only inherit one abstract class per class

// You can't instantiate an abstract class

abstract class Shape

{

public abstract double area();

// An abstract class can contain complete or default code for methods

public void sayHi()

{

Console.WriteLine("Hello");

}

// A class can have many interfaces

// An interface can't have concrete code

public interface ShapeItem

{

double area();

}

class Rectangle : Shape

{

private double length;

private double width;

public Rectangle( double num1, double num2)

{

length = num1;

width = num2;

}

public override double area()

{

return length * width;

}

// You can redefine many built in operators so that you can define what happens when you

// add to Rectangles

public static Rectangle operator+ (Rectangle rect1, Rectangle rect2)

{

double rectLength = rect1.length + rect2.length;

double rectWidth = rect1.width + rect2.width;

return new Rectangle(rectLength, rectWidth);

}

class Triangle : Shape

{

private double theBase;

private double height;

public Triangle(double num1, double num2)

{

theBase = num1;

height = num2;

}

public override double area()

{

return .5 * (theBase * height);

}

// ---------- GENERIC CLASS ----------

class KeyValue<TKey, TValue>

{

public TKey key { get; set; }

public TValue value { get; set; }

public KeyValue(TKey k, TValue v)

{

key = k;

value = v;

}

public void showData()

{

Console.WriteLine("{0} is {1}", this.key, this.value);

}

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