如何使用从字符串变量生成的函数名称调用函数

Question

In the process of automating some code, I am looking to call upon a function based on what a string is.

For example, I have a variable $somevar which is set to the string "This". Now I want to run a function doThis();

So, I was hoping I could write do.$somevar($var,$var2) . I want it to run doThis($var1,$var2) .

Is this possible?

Answer 1

You can use call_user_func to accomplish this.

call_user_func("do" . $somevar, $var1, $var2);

You can also use is_callable to check for error conditions.

if (is_callable("do" . $somevar)) {
    call_user_func("do" . $somevar, $var1, $var2);
} else {
    echo "Function do" . $somevar . " doesn't exist.";
}

Answer 2

I don't think you can do it like that, but you could do:

call_user_func('do'. $somevar, $var, $var2);

or

$func = 'do' . $somevar;
$func($var, $var2);

Answer 3

This is perfectly legal in php

$myVar = 'This';

$method = 'do'.$myVar; // = doThis
$class  = new MyClass();
$class->$method($var1, $var2, ...); // executes MyClass->doThis();

Answer 4

$fname="do$somevar";
$fname();

But you should think twice before using it.

Answer 5

In php you use -> instead of . this will work:

$foo = new someObject;
$somevar = 'function_name';
$foo->$somevar('x');

Answer 6

check call_user_func or call_user_func_array

class myclass {
    static function say_hello()
    {
        echo "Hello!\n";
    }
}

$classname = "myclass";

call_user_func(array($classname, 'say_hello'));
call_user_func($classname .'::say_hello'); // As of 5.2.3