기존 검색 엔진에 대한 PHP 호출에 대한 자세한 설명

<?php 
    $key = $_GET[&#39;key&#39;];                        //获得关键字 
    $select = $_GET[&#39;select&#39;];                  //获得搜索引擎的选择 
    switch($select)                             //根据搜索引擎的不同跳转到不同的页面 
    { 
        case "google":                          //GOOGLE 
            $url = "http://www.google.com/search?q=".$key; 
            header("Location: $url"); 
            break; 
        case "yahoo":                           //YAHOO
            $url = "http://search.yahoo.com/search?p=".$key; 
            header("Location: $url"); 
            break; 
        case "baidu":                           //百度 
            $url = "http://www.baidu.com/s?wd=".$key; 
            header("Location: $url"); 
            break; 
        default:                                //如果搜索引擎不存在，结束程序 
            break; 
    } 
?>