PHP while Loop

The PHP `while` loop is used to execute a block of code as long as a specified condition is true. It is an entry control loop, which means the condition is evaluated before entering the loop. The `while` loop is particularly useful when the number of iterations is not known beforehand.

Syntax


while (condition) {  
// code to be executed  
}

Flowchart

Example


<?php      
$n = 1;    
while ($n <= 10) {    
    echo "$n<br/>";    
    $n++;    
}      
?>

Output

1
2
3
4
5
6
7
8
9
10

Example

The `while` loop continues execution as long as the specified condition is true. If the condition is initially false, the loop body will not execute.


<?php      
$x = 5;  
while ($x < 10) {  
echo "Value is: $x<br/>";  
$x++;  
}      
?>

Output

Value is: 5
Value is: 6
Value is: 7
Value is: 8
Value is: 9

Difference between while, do-while, and for loops

while Loop do-while Loop for Loop
Executes only if the condition is true. Executes at least once, even if the condition is false. Executes a specific number of times.
Condition is checked before the loop body. Condition is checked after the loop body. Initialization, condition, and increment/decrement are set in one line.