How to implement English letter case conversion in PHP

This time I will show you how to implement the uppercase and lowercase conversion of English letters in PHP. What are the precautions for realizing the uppercase and lowercase conversion of English letters in PHP. The following is a practical case, let's take a look.

Example 1, the first letter of each word is converted to uppercase: ucwords()

<?php
$foo = &#39;hello world!&#39;;
$foo = ucwords($foo);             // Hello World!
$bar = &#39;HELLO WORLD!&#39;;
$bar = ucwords($bar);             // HELLO WORLD!
$bar = ucwords(
strtolower
($bar)); // Hello World!
?>

Example 2, the first letter of the first word is changed to uppercase: ucfirst()

<?php
$foo = &#39;hello world!&#39;;
$foo = ucfirst($foo);             // Hello world!
$bar = &#39;HELLO WORLD!&#39;;
$bar = ucfirst($bar);             // HELLO WORLD!
$bar = ucfirst(strtolower($bar)); // Hello world!
?>

Example 3, the first letter of the first word is lowercase: lcfirst()

<?php
$foo = &#39;HelloWorld&#39;;
$foo = lcfirst($foo);             // helloWorld
$bar = &#39;HELLO WORLD!&#39;;
$bar = lcfirst($bar);             // hELLO WORLD!
$bar = lcfirst(
strtoupper
($bar)); // hELLO WORLD!
?>

Change all letters to uppercase: strtoupper()
Change all letters to lowercase: strtolower()

The above introduces a total of five English letter case conversion functions, namely ucwords, ucfirst, lcfirst , strtoupper, strtolower, each has its own use.

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!

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