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PHP eval() Function


PHP Misc Reference Complete PHP Misc Reference

Definition and Usage

The eval() function evaluates a string as PHP code.

The string must be valid PHP code and must end with semicolon.

This function returns NULL unless a return statement is called in the code string. Then the value passed to return is returned. If there is a parse error in the code string, eval() returns FALSE.

Syntax

eval(phpcode)
 
Parameter Description
phpcode Required. Specifies the PHP code to be evaluated


Tips and Notes

Note: A return statement will terminate the evaluation of the string immediately.

Tip: This function can be useful for storing PHP code in a database.


Example

<?php
$string = "beautiful";
$time = "winter";
$str = 'This is a $string $time morning!';
echo $str. "<br />";
eval("\$str = \"$str\";");
echo $str;
?> 

The output of the code above will be:

This is a $string $time morning!
This is a beautiful winter morning! 


PHP Misc Reference Complete PHP Misc Reference


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