Break:

  • A break statement can be used to terminate or to come out from the loop or conditional statement unconditionally.
  • It can be used in switch statement to break and come out from the switch statement after each case expression.
  • Whenever, break statement is encounter within the program then it will break the current loop or block.
  • A break statement is normally used with if statement.
  • When certain condition becomes true to terminate the loop then break statement can be used.

Break

  • The following program demonstrates the use of break statement. Loop will be terminated as soon as the counter value becomes greater than 5.
<?php
           
   for( $i = 1; $i <= 10 ; $i++ )
   {
        if ($i > 5)
            break;    // terminate loop 
        echo "$i"."</br>" ;
   }

?>
  • break can also be used with an optional numeric argument to specify how many nested enclosing structures are to be broken out of.
  • The default value is 1, means only the immediate enclosing structure is broken out of.
<?php
        /* Using optional argument. */

$i = 0;
while ($i++)
{
    switch ($i)
    {
        case 5:
            echo "case 5 \n" ;
            break 1;     /* Exit only the switch. */
        case 10:
            echo "case 10; quitting \n" ;
            break 2;  /* Exit the switch and the while. */
        default:
            break;
    }
 }
?>

Continue:

  • A continue statement can be used into the loop when we want to skip some statement to be executed and continue the execution of above statement based on some specific condition.
  • Similar to break statement, continue is also used with if statement.
  • When compiler encounters continue, statements after continue are skipped and control transfers to the statement above continue.

Continue Statement

  • The following example uses the continue statement to print upper and lower a to z alphabets
<?php
   /* program to print upper and lower a to z alphabets using continue */

   for ( $i = 65 ; $i <= 122 ; $i++ )   // loop through ASCII value for a to z
   {
       if($i >= 91 && $i <= 96)
              continue ;       // skip unnecessary special characters.
       
          echo "| $i "."</br>" ;   // print character equivalent for ASCII value. 
   }
   
?>
  • Similar to break, continue also accepts an optional numeric argument which tells it how many levels of enclosing loops it should skip.
  • The default value is 1, which will skip to the end of the current loop.
<?php
     $i = 0 ;
     while ($i++ < 5)
     {
        echo "Outer while\n" ;
        
        while (1)
        {
            echo "Middle while\n" ;
            
            while (1)
            {
                echo "Inner while\n" ;
                continue 3;
            }
            echo "This will never output.\n" ;
        }
        echo "Not even this.\n" ;
      }
?>

Exit:

  • An exit statement is used to terminate the current execution flow.
  • As soon as exit statement is found, it will terminate the program.
  • It can be used to output a message and terminate the current script: for example exit(“Good Bye!”);
  • It can also be used with error code. For example: exit(1), exit(0376).
  • the following program demonstrates the use of exit statements.
<?php

   $filename = 'sample.txt' ;
   $file = fopen($filename, 'r')  // open file for reading
        or exit("unable to open file ($filename)");
?>

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