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:
<html>
<body>
<?php
for ($i=1; $i<=5; $i++)
{
echo "The number is " . $i . "<br />";
}
?>
</body>
</html>
|
Output:
The number is 1
The number is 2
The number is 3
The number is 4
The number is 5 |
The foreach Loop
The foreach loop is used to loop through arrays.
Syntax
foreach ($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'll be looking at the next array value.
Example
The following example demonstrates a loop that will print the values of
the given array:
<html>
<body>
<?php
$x=array("one","two","three");
foreach ($x as $value)
{
echo $value . "<br />";
}
?>
</body>
</html>
|
Output:
 |
W3Schools' Online Certification Program
The perfect solution for professionals who need to balance work, family, and career building.
More than 4000 certificates already issued!
|
The HTML Certificate documents your knowledge of HTML, XHTML, and CSS.
The JavaScript Certificate documents your knowledge of JavaScript and HTML DOM.
The XML Certificate documents your knowledge of XML, XML DOM and XSLT.
The ASP Certificate documents your knowledge of ASP, SQL, and ADO.
The PHP Certificate documents your knowledge of PHP and SQL (MySQL).
|