Monday 22 August 2011

PHP Looping - For Loops


PHP Looping - For Loops



Loops execute a block of code a specified number of times, or while a specified condition is true.

The for Loop

The for loop is used when you know in advance how many times the script should run.

Syntax

for (init; condition; increment)
  {
  code to be executed;
  }




Parameters:
  • init: Mostly used to set a counter (but can be any code to be executed once at the beginning of the loop)
  • condition: Evaluated for each loop iteration. If it evaluates to TRUE, the loop continues. If it evaluates to FALSE, the loop ends.
  • increment: Mostly used to increment a counter (but can be any code to be executed at the end of the loop)
Note: Each of the parameters above can be empty, or have multiple expressions (separated by commas).

Example

The example below defines a loop that starts with i=1. The loop will continue to run as long as i is less than, or equal to 5. i will increase by 1 each time the loop runs:


PHP Code

for ($i=1; $i<=5; $i++)
  {
  echo "The number is " . $i . "
";
  }





OUTPUT



The number is 1
The number is 2
The number is 3
The number is 4
The number is 5



The foreach Loop

The foreach loop is used to loop through arrays.
Syntax

foreach ($array as $value)
  {
  code to be executed;
  }




For every loop iteration, the value of the current array element is assigned to $value (and the array pointer is moved by one) - so on the next loop iteration, you will be looking at the next array value.

Example

The following example demonstrates a loop that will print the values of the given array:

PHP Code

$x=array("one","two","three");
foreach ($x as $value)
  {
  echo $value . "
";
  }



OUTPUT
one
two
three



try it your self



<?php
  for ($i=1; $i<=5; $i++)
  {
  echo "The number is " . $i . "<br />";
  }


//----------www.phptry.com-----------


  $x=array("one","two","three");
  foreach ($x as $value)
  {
  echo $value . "<br />";
  }


?>

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