Letter-Case conversion function in PHP

In PHP, the letter case conversion function includes: Strtolower,strtoupper,ucfirst,ucwords, and so on, this article is to introduce you to the letter case conversion function use method.

1. Convert a string to lowercase

Strtolower (): This function converts all characters passed in the string argument to lowercase and puts the string back in a small form, with the following code:

Echo strtolower ("Hello world!");

2. Turn characters into uppercase

Strtoupper (): This function, in contrast to the Strtolower function, converts the characters of the passed character argument all to uppercase and returns the string in uppercase. Using the same as Strtolowe (), the code is as follows:

<?php

$str = "Mary had A Little Lamb and She loved It so";

$str = Strtoupper ($STR);

Echo $str; Print MARY had A LITTLE LAMB and SHE loved IT so

?>

3. Convert the first character of a string to uppercase

Ucfirst (): The function is to change the first character of a string to uppercase, which returns a string with the first character capitalized. Using the same as Strtolowe (), the code is as follows:

<?php

$foo = ' Hello world! ';

$foo = Ucwords ($foo); Hello world!

Open Source Code phpfensi.com

$bar = ' HELLO world! ';

$bar = Ucwords ($bar); HELLO world!

$bar = Ucwords (Strtolower ($bar)); Hello world!

?>

4. Convert the first character of each word in a string to uppercase

Ucwords (): This function capitalizes the first character of each word of the passed-in string. Like "Hello World", after the function has been processed, "Hello Word" is returned. Usage as with Strtolowe (), the code is as follows:

<?php

$foo = ' Hello world! ';

$foo = Ucfirst ($foo); Hello world!

$bar = ' HELLO world! ';

$bar = Ucfirst ($bar); HELLO world!

$bar = Ucfirst (Strtolower ($bar)); Hello world!

?>

5. First letter lowercase Lcfirst (), the code is as follows:

<?php

$foo = ' HelloWorld ';

$foo = Lcfirst ($foo); HelloWorld

$bar = ' HELLO world! ';

$bar = Lcfirst ($bar); HELLO world!

$bar = Lcfirst (Strtoupper ($bar)); HELLO world!

?>

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