PHP Do-While Loop

1. Syntax of Do-While Loop

The basic syntax of a do-while loop is as follows:

do {
    // Code to be executed
} while (condition);

Here, the code inside the do block is executed once, and then the while condition is evaluated. If it returns true, the loop continues; if false, the loop ends.

2. Example of Do-While Loop

Let's look at a simple example to demonstrate how the do-while loop works:

$i = 1;
do {
    echo "The number is: $i
";
    $i++;
} while ($i <= 5);

In this example, the output will be:

The number is: 1
The number is: 2
The number is: 3
The number is: 4
The number is: 5

3. Important Points

• The code inside the do block is guaranteed to execute at least once.
• The condition is checked after the code block has executed.
• If the condition is false, the loop will terminate and control will move to the next statement after the loop.

4. Using Break and Continue Statements

You can use the break and continue statements within a do-while loop to control the flow of execution:

$i = 0;
do {
    $i++;
    if ($i == 3) {
        continue; // Skip the rest of the loop when $i is 3
    }
    echo "The number is: $i
";
} while ($i < 5);

This will output:

The number is: 1
The number is: 2
The number is: 4

5. Conclusion

The do-while loop is a useful control structure in PHP that ensures a block of code runs at least once before checking the condition. It's particularly beneficial in scenarios where you want to validate user input or repeatedly process data until a certain condition is met.