PHP Control Statements

PHP If Else

PHP if else statement is used to test condition. There are various ways to use if statement in PHP.

• if
• if-else
• if-else-if
• nested if

PHP If Statement

PHP if statement is executed if condition is true.

Syntax

1.            if(condition){  

2.            //code to be executed  

3.            }  

Flowchart

Example

1.            <?php  

2.            $num=12;  

3.            if($num<100){  

4.            echo "$num is less than 100";  

5.            }  

6.            ?>  

Output:

12 is less than 100

PHP If-else Statement

PHP if-else statement is executed whether condition is true or false.

Syntax

1.            if(condition){  

2.            //code to be executed if true  

3.            }else{  

4.            //code to be executed if false  

5.            }  

Flowchart

Example

1.            <?php  

2.            $num=12;  

3.            if($num%2==0){  

4.            echo "$num is even number";  

5.            }else{  

6.            echo "$num is odd number";  

7.            }  

8.            ?>  

Output:

12 is even number

PHP Switch

PHP switch statement is used to execute one statement from multiple conditions. It works like PHP if-else-if statement.

Syntax

1.            switch(expression){      

2.            case value1:      

3.             //code to be executed  

4.             break;  

5.            case value2:      

6.             //code to be executed  

7.             break;  

8.            ......      

9.            default:       

10.          code to be executed if all cases are not matched;    

11.         }  

PHP Switch Flowchart

PHP Switch Example

1.            <?php    

2.            $num=20;    

3.            switch($num){    

4.            case 10:    

5.            echo("number is equals to 10");    

6.            break;    

7.            case 20:    

8.            echo("number is equal to 20");    

9.            break;    

10.         case 30:    

11.         echo("number is equal to 30");    

12.         break;    

13.         default:    

14.         echo("number is not equal to 10, 20 or 30");    

15.         }   

16.         ?>    

Output:

number is equal to 20

PHP For Loop

PHP for loop can be used to traverse set of code for the specified number of times.

It should be used if number of iteration is known otherwise use while loop.

Syntax

1.    for(initialization; condition; increment/decrement){  

2.    //code to be executed  

3.    }  

Flowchart

Example

1.            <?php  

2.            for($n=1;$n<=10;$n++){  

3.            echo "$n<br/>";  

4.            }  

5.            ?> 

Output:

1

2

3

4

5

6

7

8

9

10

PHP Nested For Loop

We can use for loop inside for loop in PHP, it is known as nested for loop.

In case of inner or nested for loop, nested for loop is executed fully for one outer for loop. If outer for loop is to be executed for 3 times and inner for loop for 3 times, inner for loop will be executed 9 times (3 times for 1st outer loop, 3 times for 2nd outer loop and 3 times for 3rd outer loop).

Example

1.            <?php  

2.            for($i=1;$i<=3;$i++){  

3.            for($j=1;$j<=3;$j++){  

4.            echo "$i   $j<br/>";  

5.            }  

6.            }  

7.            ?>  

Output:

1 1

1 2

1 3

2 1

2 2

2 3

3 1

3 2

3 3

PHP For Each Loop

PHP for each loop is used to traverse array elements.

Syntax

1.    foreach( $array as $var ){  

2.     //code to be executed  

3.    }  

4.    ?>  

Example

1.    <?php  

2.    $season=array("summer","winter","spring","autumn");  

3.    foreach( $season as $arr ){  

4.      echo "Season is: $arr<br />";  

5.    }  

6.    ?>  

Output:

Season is: summer

Season is: winter

Season is: spring

Season is: autumn