C# Do-While Loop

After discussing the while loop in our previous tutorial, let us discuss another looping structure - do while loop in C#. In do-while loop, a block of statements or the body of loop always comes before the condition of do-while loop is tested.

Hence, during the first run of do-while loop, the body of do-while loop is always executed, even when the condition of do-while loop is false.

But from the second execution of do-while loop, the body of loop is only executed when the condition of do-while loop is true.

Note:

Similar to Java, the C# language also requires a pair of braces { } to hold more than one statement i.e. multiple statements, which are to be executed within a do-while loop.

Example of do-while loop

In the upcoming example, we are going to use do-while loop to print a series of numbers, starting from 0 to 4.

//C# Exmaple do-while loop
 

using System;

class DoWhileEx
{
public static void Main()  
{
	//Initializing the value of i
	int i=0;

	do 
	{
		Console.WriteLine("i = " + i);
		
		//Iterating the value of i
		i++;
	}while(i<5); //Condition of do-while loop

}
}

Output

i = 0
i = 1
i = 2
i = 3
i = 4

The do-while loop is executed at least once

The body of the do-while loop is always executed during its first execution, even when the condition of loop is evaluated to be false, take a look at our next example -

//C# do-while example
 

using System;

class DoWhile   
{
public static void Main()
{
	//Initializing the value of i
	int i=100;
	
	
	do 
	{
		Console.WriteLine("i = " + i);
		
		//Iterating the value of i
		i++;	

	}while(i<10);	//Condition of do-while loop

}
}