php 随意参数方法的使用

1, 用到的PHP函数: func_get_arg() / func_get_args()/ func_num_args

2, func_get_arg(index) :根据索引取得参数具体值
   <?php
function foo()
{
     $numargs = func_num_args();
     echo "Number of arguments: $numargs<br />
";
     if ($numargs >= 2) {
     echo "Second argument is: " . func_get_arg(1) . "<br />
";
     }
}

foo (1, 2, 3);
?>
  
3, func_get_args();   取得所有传入的参数,并以数组的方式反回;
 // yes, the argument list can be empty 
function foo() {     // returns an array of all passed arguments  
 $args = func_get_args();    
 foreach ($args as $k => $v) { 
  echo “arg”.($k+1).”: $v
”; 
  }   
}   
foo();  /* 没用任何输出*/   
foo(‘hello’);  /* 输出  arg1: hello  */  
foo(‘hello’, ‘world’, ‘again’);  /*输出 arg1: hello  arg2: world  arg3: again  */ 
4, func_num_args();   取得传入参数的个数;
 <?
function foo()
{
    $numargs = func_num_args();
    echo “Number of arguments: $numargs
“;
}

foo(1, 2, 3);    // Prints ‘Number of arguments: 3′
?>
 
5, 综合实例
 <?php
function foo()
{
    $numargs = func_num_args();//得到参数的个数
    echo "Number of arguments: $numargs<br />
";
    if ($numargs >= 2) {
        echo "Second argument is: " . func_get_arg(1) . "<br />
";
    }
    $arg_list = func_get_args();
    for ($i = 0; $i < $numargs; $i++) {
        echo "Argument $i is: " . $arg_list[$i] . "<br />
";
    }
}

foo(1, 2, 3);
?>
原文地址:https://www.cnblogs.com/qianlizeguo/p/6834570.html