C# for Loop

A for loop is used to execute the program for a fixed number of times. For loop in C# is similar to that in C, C++ or Java.

Syntax

A for loop has three parts.

1. Initialization
2. Condition and
3. An operation to be performed each time the loop is executed.

for(int i=0; i<10; i++){
	//statements
}

Working

This is how a for loop works:

• A value is initialized (only for the first time).
• An expression is evaluated.
• The body of the loop is executed if the expression is evaluated to true.
• An operation (increment or decrement) is performed.
• The above three steps are repeated until the expression is evaluated to false.

See this post to find the difference between a for loop and while loop.

Example

using System;
namespace CSharpExamples
{
    class Program
    {
        static void Main(string[] args)
        {
            for(int i=0;i<=3;i++)
            {
                Console.WriteLine("value of i is: " + i);
            }
        }
    }
}

This program, when executed will produce the following output:

value of i is: 0
value of i is: 1
value of i is: 2
value of i is: 3

Nested for loop

A for loop specified inside a for loop is known as a nested for loop.

Example

using System;
namespace CSharpExamples
{
    class Program
    {
        static void Main(string[] args)
        {
            for(int i=2;i>=0;i--)
            {
                for(int j=0;j<2;j++)
                {
                    Console.WriteLine("i = " + i + ", j = " + j);
                }
            }
            Console.ReadLine();
        }
    }
}

The output of this program is:

i = 2, j = 0

i = 2, j = 1

i = 1, j = 0

i = 1, j = 1

i = 0, j = 0

i = 0, j = 1