PHP Introduction - Lecture #6

PHP - LOOPS

Hello All... welcome every one. I'm going to start PHP lectures for Very Beginners, who wants to learn PHP from very beginning. No matter if you do not have any basic programming concept. If you follow my tutorials I hope you will surely get some how good knowledge of PHP.

Today our Topic is

LOOPS

The term `loop` is defined as “Repetition of anything”. Here in PHP we use loops when we have to print something multiple times by writing them just single time within a loop.

In almost every programming language there are 4 types of loops.

1-    While Loop

2-    Do-while Loop

3-    For Loop

4-    For each Loop

The last one For each loop will be studied in next coming topic `Arrays` but here we will focus of first three types of loops.

i-                   While loop: This loop works when the specified condition defined in loop syntax is true.

Here is simple syntax

            while( condition )

{

            Code you wants to execute

}

The code within the curly braces will be executed if the condition defined in the above brackets is true. Let’s take an example of first while loop.

First start the php

<?php

            $a = 1;

            while($a < 10){

            echo $a;

            $a++;

}

?>

Description of above code:

First of all we have declared a variable named `a` and assigned value of 1

After then while loop is started with `while` keyword and inside the brackets there is condition defined that $a declared above is less than 10 or not if it’s less than 10 means condition is true if condition is true then remaining part of code will be executed. After while condition is true there is echo statement that prints $a variable and $a will be printed unless and until while condition becomes false. And in last $a++ this is called an increment operator. Increment operator increases the value by adding +1 in the defined value. So variable a will also increase by means of +1.

Here is the code and result of it

The result is up to 9 because if it comes to 10 and look at the condition that says $a < 10 when it becomes 10 then 10 < 10 this condition becomes false and the code execution is stopped. While loop executes the code until condition is true. In simple while loop first checks the condition and then executes the code. Similarly you can print multiple statements using while loop in `echo` statement by creating your own login.

Thanks Guys. Any thing missing or any question from this topic you can comment below, I will be trying to solve and answer your question.

Our Next topic will be `do-while Loop`.

Good Luck J