using System;

public class Program

{

    public static void Main()

    {

              //Beginner - Strings

​

        //All examples below return a new strings, they do not modify the original string.

        var fullName = "Arturas Morozovas ";

        //Trim -- Removes any blank spaces on the outside of the string

            Console.WriteLine("Using Trim - Trim: '{0}'",fullName.Trim());

        //Without Trim

            Console.WriteLine("Not Using - Trim:  '{0}'", fullName);

        //ToUpper

            Console.WriteLine();

            Console.WriteLine("Using ToUpper - To Upper: {0}",fullName.ToUpper());

        //ToLower

            Console.WriteLine("Using ToLower - To Lower: {0}", fullName.ToLower());

​

        //Split into first and last name

​

        //IndexOf() - More difficult split but contains better functionality if something complex comes up.

​

        var index = fullName.IndexOf(' '); //Finds a location of a first blank space

        //Substring - Second overload.

        var firstName = fullName.Substring(0, index); //This method has two overloads. We use second one that specifies starting and ending position. Ending being the position of a blank space. 

        var lastName = fullName.Substring(index +1); //This is the first overload. We use index + 1 as it initially starts at the blank space and we want to remove it.

        Console.WriteLine();

        Console.WriteLine("Using IndexOf & Substring - First name :" + firstName);

        Console.WriteLine("Using IndexOf & Substring - Last Name  :" + lastName);

​

        //Using Split Method which is much more simple

​

        string[] names = fullName.Split(' ');

        Console.WriteLine();

        Console.WriteLine("Using Split - First name: " + names[0]);

        Console.WriteLine("Using Split - Last name: " + names[1]);

​

        //Replace

        Console.WriteLine();

        Console.WriteLine("Replace Arturas to Arturo        : " + fullName.Replace("Arturas", "Arturo"));

        Console.WriteLine("Replace A with a                 : " + fullName.Replace("A", "a"));

        Console.WriteLine("Replace blank space with nothing : " + fullName.Replace(" ", ""));   //Exact as applying the trim method

​

        //IsNullOrEmpty -- Outdated method

        Console.WriteLine();

        if (String.IsNullOrEmpty(null) || String.IsNullOrEmpty("") || String.IsNullOrEmpty(" ".Trim()))     //Value is null or nothing retuns a true and displays a message.

        //I have also trimmed a whitespace as this would get neglected and would get passed through.

            Console.WriteLine("IsNullOrEmpty     : Invalid");

​

        //IsNullOrWhiteSpace -- To use method.

        if (String.IsNullOrWhiteSpace(null) || String.IsNullOrWhiteSpace(" "))   //Value is null or nothing retuns a true and displays a message.

            Console.WriteLine("IsNullOrWhiteSpace: Invalid");

​

        //Convert Numbers to Strings

        Console.WriteLine();

        string str = "25";

        int age = Convert.ToInt32(str);

        Console.WriteLine("String to Number                        :" + age);

​

        //Convert Strings to Numbers

        float price = 29.95f;

        //Regular conversion

        string stringPrice = price.ToString();

        Console.WriteLine("From number to string                   :" + stringPrice);

        //Formatted conversion 

        //https://docs.microsoft.com/en-us/dotnet/standard/base-types/standard-numeric-format-strings

        string formattedStringPrice = price.ToString("C");

        string formattedRoundedStringPrice = price.ToString("C0");

        Console.WriteLine("From number to converted string         :" + formattedStringPrice);

        Console.WriteLine("From number to converted rounded String :" + formattedRoundedStringPrice);

        //String Lesson - Since strings are immutable, ToUpper() will return a new string with all uppercase letters.

        //But we've not stored the result here, and since the name variable will be unchanged

        Console.WriteLine();

        var name = "Arturo";

​

        name.ToUpper();

​

        Console.WriteLine(name);

        //String to a char array

        Console.WriteLine("Enter a string to be converted to char");

        string namee = Console.ReadLine();

​

        //Creates an array of chars from a string

        //string.ToCharArray(); creates the array.

        char[] nameCharArray = namee.ToCharArray();

        foreach (var element in nameCharArray)

            Console.WriteLine(element);

    }

}