PHP converts the uppercase and lowercase letters of a string to an instance.

PHP converts the uppercase and lowercase letters of a string to an instance.

The first letter of each word is converted to uppercase:Ucwords ()

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

The first letter of a word is capitalized:Ucfirst ()

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

The first letter of a word becomes smaller:Lcfirst ()

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

Uppercase for all letters:Strtoupper ()

All letters should be written as follows:Strtolower ()

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