Using break keyword: The break keyword is used to immediately terminate the loop and the program control resumes at the next statement following the loop. To terminate the control from any loop we need to use break keyword. The break keyword is used to end the execution of current for, foreach, while, do-while or switch structure. But in nested loops, to exit out from all or some of the outer loops, we need to pass a numeric argument which tells it how many nested enclosing structures are to be terminated.
Syntax:
break number_of_nested_loop_to_terminate;
Parameters: The break keyword followed by a numeric argument which is by default 1. Passing of variables and 0 as a numeric argument is not allowed.
Examples:
break 2; // It terminates second outer loop break 3; // It terminates third outer loop break $num; // Variable cannot be used as numeric argument since version 5.4.0 break 0; // 0 is not a valid argument to pass
Below programs illustrate how to break outer loops in PHP:
Program 1: PHP program to display the number while inner loop is not terminated.
<?php // Initialize a number $num = 10; // Outer loop to iterate $num times for( $i = 0; $i < 10; $i++ ) { // Initialize a variable $j $j = 1; // Inner loop while( $j <= 3 ) { if( $i >= 1 ) // Breaking the outer loop break 2; echo $j . " "; $j++; } } ?> |
1 2 3
Program 2: PHP program to search a number in an array and break the outer loop when it is found.
<?php // Create a 2D array $arr = array( array (105, 96, 112), array(96, 45, 63) ); // Initialize a number which // need to fine in the array $num = 45; // Declare a boolean variable and // initialize it with false $found = FALSE; // Outer loop for($i = 0; $i < 2; $i++) { // Inner loop for($j = 0; $j < 3; $j++) { if($num == $arr[$i][$j]) { $found = TRUE; // Terminate the outer loop break 2; } } } // Check number is found or not if( $found ) echo $num . " is found in the array"; else echo $num . " is not found in the given array"; ?> |
45 is found in the array
Using goto keyword: The goto keyword is used to jump the section of the program. It jumps to the target label.
Program 3: PHP program to break the outer loop using goto keyword.
<?php // Create a 2D array $arr = array( array (105, 96, 112), array(96, 45, 63) ); // Initialize a number which // need to fine in the array $num = 45; // Declare a boolean variable and // initialize it with false $found = FALSE; // Outer loop for($i = 0; $i < 2; $i++) { // Inner loop for($j = 0; $j < 3; $j++) { if($num == $arr[$i][$j]) { $found = TRUE; // Terminate the outer loop // using goto keyword goto terminateLoop; } } } // target label terminateLoop: // Check number is found or not if( $found ) echo $num . " is found in the array"; else echo $num . " is not found in the given array"; ?> |
45 is found in the array
