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php tutorial function call_user_func and call_user_func_array
The call_user_func function is similar to a special method of calling a function. The method of use is as follows:
function a($b,$c)
{
echo $b;
echo $c;
}
call_user_func('a', "111","222");
call_user_func('a', "333","444");
//Display 111 222 333 444
?>

It is strange to call the method inside the class. It actually uses array. I don’t know what the developer thought about it. Of course, new is omitted, which is also full of novelty:
class a {
function b($c)
{
echo $c;
}
}
call_user_func(array("a", "b"),"111");
//Display 111
?>

The call_user_func_array function is very similar to call_user_func, except that the parameters are passed in a different way to make the parameter structure clearer:
function a($b, $c)
{
echo $b;
echo $c;

}
call_user_func_array('a', array("111", "222"));
//Display 111 222
?>

The call_user_func_array function can also call methods within the class

Class ClassA
{

function bc($b, $c) {
$bc = $b + $c;
echo $bc;
}
}
call_user_func_array(array('ClassA','bc'), array("111", "222"));

//Display 333
?>

Both the call_user_func function and the call_user_func_array function support references, which makes them more functionally consistent with ordinary function calls:
function a(&$b)
{
$b++;
}
$c = 0;
call_user_func('a', &$c);
echo $c;//display 1
call_user_func_array('a', array(&$c));
echo $c;//display 2

Simple usage of call_user_func_array in php
Today in the group, a person named Lewis asked about the usage of call_user_func_array. Since I had never used it before, I couldn’t say anything, so I looked at the manual and found that it was written like this:

call_user_func_array
(PHP 4 >= 4.0.4, PHP 5)

call_user_func_array -- Call a user function given with an array of parameters
Description
mixed call_user_func_array ( callback function, array param_arr )


Call a user defined function given by function, with the parameters in param_arr.
Then there is another example:

I believe you should understand a little bit after reading the examples, right?


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