Question

How to check if string is empty in C#

Answer 1

using System;
 
public class Program
{
    static void Main(string[] args)
    {
        try {
            string s = null;
 
            if (s == string.Empty) {
                Console.WriteLine("yes");
            }
            else {
                Console.WriteLine("no"); 
            }
        }
        catch (Exception ex) {
            Console.WriteLine(ex.Message);
        }  
    }
}



/*
run:

no
  
*/

70+ SQL courses for beginners and professionals

Answer 2

using System;
 
public class Program
{
    static void Main(string[] args)
    {
        try {
            string s = "";
 
            if (s == string.Empty) {
                Console.WriteLine("yes");
            }
            else {
                Console.WriteLine("no"); 
            }
        }
        catch (Exception ex) {
            Console.WriteLine(ex.Message);
        }  
    }
}



/*
run:

yes
  
*/

70+ SQL courses for beginners and professionals

Answer 3

using System;
 
public class Program
{
    static void Main(string[] args)
    {
        try {
            string s = string.Empty;
 
            if (s == string.Empty) {
                Console.WriteLine("yes");
            }
            else {
                Console.WriteLine("no"); 
            }
        }
        catch (Exception ex) {
            Console.WriteLine(ex.Message);
        }  
    }
}



/*
run:

yes

*/
  

70+ SQL courses for beginners and professionals

Answer 4

using System;
 
public class Program
{
    static void Main(string[] args)
    {
        string s = "";
 
        if (s == "") {
            Console.WriteLine("empty 1");
        }
 
        if (s.Equals("")) {
            Console.WriteLine("empty 2");
        }
 
        if (string.Equals(s, "")) {
            Console.WriteLine("empty 3");
        }
 
        if (s.Length == 0) {
            Console.WriteLine("empty 4");
        }
 
        if (string.IsNullOrEmpty(s)) {
            Console.WriteLine("empty 5");
        }
    }
}



/*
run:

empty 1
empty 2
empty 3
empty 4
empty 5
  
*/

 

70+ SQL courses for beginners and professionals