(PHP 5 >= 5.3.0)
lcfirst — 使一个字符串的第一个字符小写
$str
)
返回str的第一个字符小写了的字符串。如果str的第一个字符是字母，则将其转换为小写。
需要注意的是“字母”是由当前语言区域决定的。比如，在默认的“C”区域像日耳曼语系中的元音变音a (?) 将不会被转换。
str
输入的字符串。
返回转换后的字符串。
Example #1 lcfirst() 例子：
<?php
$foo = 'HelloWorld';
$foo = lcfirst($foo); // helloWorld
$bar = 'HELLO WORLD!';
$bar = lcfirst($bar); // hELLO WORLD!
$bar = lcfirst(strtoupper($bar)); // hELLO WORLD!
?>
phpnet at katylavallee dot com (2009-04-02 08:50:42)
Easiest work-around I've found for <5.3:
<?php
$string = "CamelCase"
$string{0} = strtolower($string{0})
echo $string; // outputs camelCase
?>
ahlers_wim at hotmail dot com (2008-11-22 21:48:49)
As of PHP release 6 direct reference modification is not permitted any more.
Reference modification is the process of manipulating characters within a string by means of the instruction such as:
$str[0] in the code line: $str[0] = strtolower($str[0]);
For this reason I have recoded the lcfirst function (on function_exists('lcfirst') === false) as follows:
<?php
if ( false === function_exists('lcfirst') ):
function lcfirst( $str )
{ return (string)(strtolower(substr($str,0,1)).substr($str,1));}
endif;
?>
Remarks:
Also notice that I have used the more modern scope delimeters (if:-endif;) and I have also removed the unnecessary intermediate result. That is, the manipulation is returned directly.
alex aulbach (2008-10-06 09:20:50)
In some cases maybe more useful?
$lower = strtolower( substr($upper,0,1) ) . substr($upper,1);
harmor (2008-05-05 15:43:12)
A slight modification from Northie's post here ( http://us2.php.net/manual/en/function.ucfirst.php#68443), where lcfirst may not exist in your PHP build:
<?php
if(false === function_exists('lcfirst'))
{
/**
* Make a string's first character lowercase
*
* @param string $str
* @return string the resulting string.
*/
function lcfirst( $str ) {
$str[0] = strtolower($str[0]);
return (string)$str;
}
}
/* Tests */
echo var_dump(lcFirst(NULL)).'<br />'; /* string(0) "" */
echo var_dump(lcFirst('')) .'<br />'; /* string(0) "" */
echo var_dump(lcFirst('S')) .'<br />'; /* string(1) "S" */
echo var_dump(lcFirst('?')) .'<br />'; /* string(0) "?" */
echo var_dump(lcFirst('Hello World!!!')); /* string(14) "hello World!!!" */