The use and case of uppercase and lowercase conversion functions in PHP

The Strtoupper () function converts the string to uppercase and the Strtolower function: The function converts all characters of the passed-in string argument to lowercase and returns the string in a small form. Below through this article to share the PHP case conversion function (Strtolower, strtoupper) usage, need to refer to the friend

1, convert the string to lowercase

Strtolower function: This function converts all characters passed in the string argument to lowercase and puts the string back in a small form.

Example:

<?php  $str = "I want to FLY";  $str = Strtolower ($STR);  echo $str;//by www.jb51.net?>

Output:

I want to fly

2, turn the character into uppercase

Strtoupper function: This function, in contrast to the Strtolower function, converts the character of the passed character argument all to uppercase and returns the string in uppercase.

Use the same as Strtolower ().

Two useful functions are described below.

3, converts the first character of the string to uppercase

Ucfirst function: The function is to change the first character of a string to uppercase, which returns a string with the first character capitalized.

Usage is similar to the Strtolower () function.

4, converts the first character of each word in a string to uppercase

Ucwords: This function capitalizes the first character of each word in the passed-in string. such as "Hello World", after the function is processed, will return "Hello Word."

Usage is similar to Strtolower ().

Focus on the most commonly used functions

When writing a PHP program, it is often necessary to convert some strings into uppercase and lowercase, and here are a few of the most commonly used functions

Strtolower ()//convert string to lowercase

Strtoupper ()//convert string to uppercase

Ucfirst ()//converts the first character of a string to uppercase

Ucwords ()//converts the first letter of each word in a string to uppercase

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