请问这个php程式为什么会出错。

PHP code

$s2 = "make_by_id";echo convString($s1);function convString($string){    $array = explode('_', $string);    array_walk($array, "ucwords");    return implode('', $array);}

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Warning: Wrong parameter count for ucwords() in E:\wwwroot\webtest\test.php on line 25

[解决办法]

PHP code

$arr2    = explode('_', $s2);function self_ucwords(&$p_a, $p_b)//通常传入2参数，也可以3个参数，更详细用法查手册{    $p_a    = ucwords($p_a);//一个参数}array_walk($arr2, 'self_ucwords');echo    implode('', $arr2);
[解决办法]


$array = explode('_', $string);

array_walk($array, "ucwords");


$array前加多个$array=array();