Do-While Loop

When we need to run a loop at least once, then we use the Do-while loop in a PowerShell.

The Do-While loop is a looping structure in which a condition is evaluated after executing the statements. This loop is also known as the exit-controlled loop.

The do-while loop is the same as while loop, but the condition in a do-while loop is always checked after the execution of statements in a block.

The Do keyword is also used with the ‘Until‘ keyword to run the statements in a script block. Like a Do-while loop, the Do-until loop also executes at least once before the condition is evaluated. The Do-Until loop executes its statements in a code block until the condition is false. When the condition is true, the loop will terminate.

We can use the flow control keywords such as Break and Continue in a Do-while or Do-until loop.

Syntax

The following block shows the syntax of Do-while loop:

The following block shows the syntax of Do-until loop:

Flowchart of Do-While loop

Flowchart of Do-Until loop

Examples

The following examples describe how to use the Do-while and Do-until loop in the PowerShell:

Example1: In this example, we print the values of an integer from 1 to 10.

Output:

1  2  3  4  5  6  7  8  9  10  

Example2: In this example, we will print the values of an array using Do until loop.

Output:

1  2  3  4  5  6  7  

Example3: In this example, we print the table of 5 by using the Do-while loop.

Output:

5 * 1 = 5  5 * 2 = 10  5 * 3 = 15  5 * 4 = 20  5 * 5 = 25  5 * 6 = 30  5 * 7 = 35  5 * 8 = 40  5 * 9 = 45  5 * 10 = 50  

In this example, we have printed the multiplication table of 5 using a Do-while loop. First, we have created and initialized a variable $table and $i with the values 5 and 1 respectively. Then we have written a do-while loop.

In a loop, we have an echo command that will print the result of $res, which stores the multiplication of $table * $i.

Each time, the value of the variable $i is increased by 1, and the condition is checked. When the value of variable $i becomes 11, the condition becomes false, and the loop is terminated.