Some PHP functions and features you never knew_PHP Tutorial

The real power of PHP comes from its functions, but some PHP functions are not fully utilized, and not everyone will read the manual and function reference page from beginning to end. Here we will introduce it to you These useful functions and functions.

1. Function with any number of parameters

As you may already know, PHP allows defining functions with optional parameters. But there are also methods that completely allow any number of function parameters. The following are examples of optional parameters:

1. The following is the quoted content:
3. //functionwith2optionalarguments
4. functionfoo($arg1=”,$arg2=”){
6. echo "arg1:$arg1 ”;
7. echo "arg2:$arg2 ”;
9. }
11. foo(‘hello’,world’);
12. /*prints:
13. arg1:hello
14. arg2:world
15. */
17. foo();
18. /*prints:
19. arg1:
20. arg2:
21. */

Now let’s see how to create a function that accepts any number of arguments. This time you need to use the func_get_args() function:

1. The following is the quoted content:
3. //yes,theargumentlistcanbeempty
4. functionfoo(){
6. //returnsanarrayofallpassedarguments
7. $args=func_get_args();
9. foreach($argsas$k=>$v){
10. echo “arg”.($k+1).”:$v ”;
11. }
13. }
15. foo();
16. /*printsnothing*/
18. foo(‘hello’);
19. /*prints
20. arg1:hello
21. */
23. foo(‘hello’, ‘world’, ‘again’);
24. /*prints
25. arg1:hello
26. arg2:world
27. arg3:again
28. */