Function handling 函数
PHP 手册

func_get_arg

(PHP 4, PHP 5)

func_get_argReturn an item from the argument list

说明

mixed func_get_arg ( int $arg_num )

Gets the specified argument from a user-defined function's argument list.

This function may be used in conjunction with func_get_args() and func_num_args() to allow user-defined functions to accept variable-length argument lists.

参数

arg_num

The argument offset. Function arguments are counted starting from zero.

返回值

Returns the specified argument, or FALSE on error.

更新日志

版本 说明
5.3.0 This function can now be used in parameter lists.

错误/异常

Generates a warning if called from outside of a user-defined function, or if arg_num is greater than the number of arguments actually passed.

范例

Example #1 func_get_arg() example

<?php
function foo()
{
     
$numargs func_num_args();
     echo 
"Number of arguments: $numargs<br />\n";
     if (
$numargs >= 2) {
         echo 
"Second argument is: " func_get_arg(1) . "<br />\n";
     }
}

foo (123);
?>

注释

Note: Because this function depends on the current scope to determine parameter details, it cannot be used as a function parameter. If this value must be passed, the results should be assigned to a variable, and that variable should be passed.

Note: This function returns a copy of the passed arguments only, and does not account for default (non-passed) arguments.

参见


Function handling 函数
PHP 手册