PHP Loops: for, foreach, while, do…while

In PHP loops, are used to execute the certain portion of the code number of times until certain condition are met.

The types of loops are:

For Loop

In PHP, for loop is used to perform some tasks repeatedly for a specific number of times.
For loop is used, when you know in advance, how many times to repeat the task.

Syntax:-

<?php
	for(initialization; condition; increment/decrement counter){
		//block of code that is executed repeatedly
	}
?>

Flowchart:-

Example:-

<?php
	for($i=25; $i<=35; $i++){
		echo "$i <br/>";
	}
?>

Output:-

25
26
27
28
29
30
31
32
33
34
35

In PHP, for each loop is used to loop over all the elements of an array.
For each loop is used, if you want to perform some task repeatedly for each element of an array.
Starting from first element of array, it iterates through each element in the array

Syntax:-

<?php
	foreach($arrayname as $value){
		//block of code that is executed repeatedly
	}
?

<?php
	for each($arrayname as $key = $value){
		//block of code that is executed repeatedly
	}
?>

Flowchart:-

Example:-

Here we create array with five elements and print that array.

<?php
	$number = array(50,60,70,80,90);
	foreach($number as $value){
		echo $value. "<br/>";
 	}
?>

Output:-

50
60
70
80
90

In PHP, while loop is used to repeatedly perform some task until condition within while loop is satisfied.
While loop will execute the code if and only if a specified condition is true otherwise it will be terminated.

Syntax:

<?php
	Initialization;
	while(condition){
		//block of code 
		Increment/decrement counter;
	}
?>

Flowchart:-

Example:-

Here we print 25 to 30 numbers using while loop.

<?php
	$number = 25;
	while($number <= 30){
		echo "$number <br/>";
		$number++;
 	}
?>

Output:-

25
26
27
28
29
30

In PHP, do…while loop is used to repeatedly perform some task until condition within do…while loop is satisfied.
In do…while loop, even if the condition is false, the block of code will be executed at least one time.

Syntax:-

<?php
	Initialization;
	do{
		//block of code 
		Increment/decrement counter;
	}
	while(condition);
?>

Flowchart

Example:-

Here we print 25 to 30 numbers using do…while loop.

<?php
	$number = 25;
	do{
		echo "$number <br/>";
		$number++;
 	}
	while($number <= 30)
?>

Output:-

25
26
27
28
29
30