Php Loops

    
     This article will show you how php loops are working

  • while
    • The while loop executes a block of code while a condition is true.
    Syntax:
    while (condition)
      {   code that will be executed;   }

    Example

    This example  defines a loop that starts with i=1. The loop will continue 
to run until i is less than, or equal to 5. i will increase by 1 in each iteration:

<html>
<body>
<?php

$k=1;
while($k<=5)
   {
  echo "The loop number is " . $k . "<br />";
  $k++;
  }

?>
</body>
</html>
    Result:
    The loop number is 1
    The loop number is 2
    The loop number is 3
    The loop number is 4
    The loop number is 5

  • do...while
    • The do...while statement will always execute the block of code once, then check the condition, and repeat the loop while the condition is true.
    Syntax:
    do
    { 
      code that will be executed;
    }
    while (condition);

    Example


    The example below defines a loop that starts with i=1. It will then increment 
i with 1, and write some result. Then condition is checked, and the loop 
will continue to run until i is less than, or equal to 5:

<html>
<body>
<?php

$k=1;
do
   {
  $k++;
  echo "The loop number is " . $k . "<br />";
  }
while ($k<=5);

?>
</body>
</html>
    Result:
    The loop number is 2
    The loop number is 3
    The loop number is 4
    The loop number is 5
    The loop number is 6

  • for
    • The for loop is used when you know in advance how many times the script should run.
    Syntax:
    for (init; condition; increment)
    {
      code that will be executed;
    }

    Example

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

<html>
<body>
<?php

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

?>
</body>
</html>
    Result:
    The loop number is 1
    The loop number is 2
    The loop number is 3
    The loop number is 4
    The loop number is 5

  • foreach
    • The foreach loop is used to loop through arrays.
    Syntax:
    foreach ($array as $value)
    {
      code that will be executed;
    }
    For every iteration, the value of the current array element is assigned to $value (and the array pointer is moved by one) - so on the next iteration, you will be point to next value.

    Example 


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

<html>
<body>
<?php

$x=array("First","Second","Third");
foreach ($x as $value) 
 {
  echo $value . "<br />"; 
}

?>
</body>
</html>
    Result:
    First
    Second
    Third
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