call_user_func函数的注意事项
call_user_func函数的注意事项
parse error: syntax error, unexpected t_list, expecting t_string in
今天在使用这个函数的时候一直提示上述问题。参看官方的手册也没有介绍使用其的注意事项。
附:
mixed call_user_func ( callback $function [, mixed $parameter [, mixed $... ]] )
可以传递任何内置的或者用户自定义的函数,除了语言结构如array(),echo(),empty(),eval(),exit(),isset(),list(),print() 和 unset()。
本人的问题就是在对象中存在一个叫list的方法名。故其和php教程的语言结构list()起冲突了。
看实例应用
call_user_func函数类似于一种特别的调用函数的方法,使用方法如下:
function a($b,$c)
{
echo $b;
echo $c;
}
call_user_func('a', "111","222");
call_user_func('a', "333","444");
//显示 111 222 333 444
?>
调用类内部的方法比较奇怪,居然用的是array,不知道开发者是如何考虑的,当然省去了new,也是满有新意的:
class a {
function b($c)
{
echo $c;
}
}
call_user_func(array("a", "b"),"111");
//显示 111
?>
call_user_func_array函数和call_user_func很相似,只不过是换了一种方式传递了参数,让参数的结构更清晰:
function a($b, $c)
{
echo $b;
echo $c;
}
call_user_func_array('a', array("111", "222"));
//显示 111 222
?>

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