Call_user_function () method

Call_user_func (Callback $ function [, mixed $ parameter [, mixed $...])

Call the user-defined function provided by the first parameter.
Return Value: return the result of calling the function, or false.

Example:

PHP code

1. <? PHP
2. Function eat ($ fruit) // you can specify multiple parameters.
3. {
4. Echo "you want to eat $ fruit, no problem ";
5. }
6. Call_user_func ('eid', "apple"); // print: You want to eat apple, no problem;
7. Call_user_func ('eid', "orange"); // print: You want to eat orange, no problem;
8. ?>

 

Internal method of the call class:

PHP code

1. <? PHP
2. Class myclass {
3. Function say_hello ($ name)
4. {
5. Echo "Hello! $ Name ";
6. }
7. }
9. $ Classname = "myclass ";
11. // Use array (Class Name, method name) to call functions inside the class)
12. Call_user_func (Array ($ classname, 'Say _ hello'), 'dain _ Sun ');
14. // Print hello! Dain_sun
16. ?>

 



The call_user_func_array function is similar to call_user_func,Array UsedTo make the parameter structure clearer:

Call_user_func_array(Callback $ function, array $ param_arr)

Call a user-defined function. The parameter format is array.
Return Value: return the result of calling the function, or false.

PHP code

1. <? PHP
3. Function debug ($ var, $ Val)
4. {
5. Echo "variable: $ var <br> value: $ Val <br> ";
6. Echo "<HR> ";
7. }
10. $ Host = $ _ server ["SERVER_NAME"];
11. $ File = $ _ server ["php_self"];
13. Call_user_func_array ('debug', array ("host", $ host ));
14. Call_user_func_array ('debug', array ("file", $ file ));
17. ?>

 

The internal method of the call class is the same as that of the call_user_func function. It is called using arrays.

Exmaple:

PHP code

1. <? PHP
3. Class Test
4. {
5. Function debug ($ var, $ Val)
6. {
7. Echo "variable: $ var <br> value: $ Val <br> ";
8. Echo "<HR> ";
9. }
10. }
12. $ Host = $ _ server ["SERVER_NAME"];
13. $ File = $ _ server ["php_self"];
15. Call_user_func_array (Array ('test', 'debug'), array ("host", $ host ));
16. Call_user_func_array (Array ('test', 'debug'), array ("file", $ file ));
18. ?>

 



Note: call_user_func and call_user_func_array Functions Support reference.

PHP code

1. <? PHP
2. Function increment (& $ var)
3. {
4. $ Var ++;
5. }
7. $ A = 0;
8. Call_user_func ('credentials', $ );
9. Echo $ A; // 0
11. Call_user_func_array ('secret', array (& $ A); // you can use this instead
12. Echo $ A; // 1
13. ?>