PHP strtolower()Function

PHP String 参考手册PHP String Reference Manual

Examples

Convert all characters to lowercase:

<?php
echo strtolower("Hello WORLD.");
?>

Run Example »

Definition and Usage

The strtolower() function converts a string to lowercase.

Note:This function is binary-safe.

Related functions:

  • strtoupper()- Converts a string to uppercase
  • lcfirst()- Converts the first character of a string to lowercase
  • ucfirst()- Converts the first character of a string to uppercase
  • ucwords() - Converts the first character of each word in a string to uppercase

Syntax

strtolower(string)

Parameter Description
string Required. Specifies the string to convert.

Technical Details

Return value: Returns the string converted to lowercase.
PHP Version: 4+


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