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  • 跨域请求的三种解决办法

    第一种:jsonp的方式

    <?php
        header('Content-type: application/json');
        //获取回调函数名
        $jsoncallback = $_GET['jsoncallback'];
        //json数据
        $json_data = '{"data":[{"did":"29","deptName":"u8f6fu4ef6u90e8"},
        {"did":"30","deptName":"u8f6fu4ef6u90e8"},
        {"did":"31","deptName":"u6d4bu8bd5u90e8"},
        {"did":"32","deptName":"u786cu4ef6u90e8"},
        {"did":"33","deptName":"u54c1u8d28u90e8"},
        {"did":"34","deptName":"u786cu4ef6u90e8"},
        {"did":"35","deptName":"u5236u9020u4e2du5fc3"},
        {"did":"36","deptName":"u91c7u8d2du90e8"},
        {"did":"37","deptName":"u751fu4ea7u90e8"},
        {"did":"38","deptName":"u603bu7ecfu529e"},
        {"did":"39","deptName":"u9500u552eu90e8"},
        {"did":"40","deptName":"u8d22u52a1u90e8"},
        {"did":"41","deptName":"u4f01u5212u90e8"},
        {"did":"42","deptName":"u8bbeu8ba1u90e8"},
        {"did":"43","deptName":"u4ebau8d44u90e8"},
        {"did":"44","deptName":"u884cu653fu90e8"},
        {"did":"45","deptName":"u4ebau4e8bu90e8"},
        {"did":"46","deptName":"u7ef4u4feeu90e8"},
        {"did":"47","deptName":"u4ed3u50a8u90e8"}]}';
        //输出jsonp格式的数据
        echo $jsoncallback . "(" . $json_data . ")";
    ?>

    第二种:在后端添加允许跨域的请求头

    <?php
        // 允许 com.qq 发起的跨域请求
        //header("Access-Control-Allow-Origin: com.qq"); 
        // 允许 所有 发起的跨域请求
        header("Access-Control-Allow-Origin: *");
        echo '{"data":[{"did":"29","deptName":"u8f6fu4ef6u90e8"},
        {"did":"30","deptName":"u8f6fu4ef6u90e8"},
        {"did":"31","deptName":"u6d4bu8bd5u90e8"},
        {"did":"32","deptName":"u786cu4ef6u90e8"},
        {"did":"33","deptName":"u54c1u8d28u90e8"},
        {"did":"34","deptName":"u786cu4ef6u90e8"},
        {"did":"35","deptName":"u5236u9020u4e2du5fc3"},
        {"did":"36","deptName":"u91c7u8d2du90e8"},
        {"did":"37","deptName":"u751fu4ea7u90e8"},
        {"did":"38","deptName":"u603bu7ecfu529e"},
        {"did":"39","deptName":"u9500u552eu90e8"},
        {"did":"40","deptName":"u8d22u52a1u90e8"},
        {"did":"41","deptName":"u4f01u5212u90e8"},
        {"did":"42","deptName":"u8bbeu8ba1u90e8"},
        {"did":"43","deptName":"u4ebau8d44u90e8"},
        {"did":"44","deptName":"u884cu653fu90e8"},
        {"did":"45","deptName":"u4ebau4e8bu90e8"},
        {"did":"46","deptName":"u7ef4u4feeu90e8"},
        {"did":"47","deptName":"u4ed3u50a8u90e8"}]}';
    ?>

    第三种:代理请求,由后端去访问要跨域的请求的内容并返回,然后页面访问本地后端

    <?php
        $url='http://192.168.192.130/test2.php';
    
        $html= file_get_contents($url);
        
        echo $html;
    ?>

    页面调用方式:

    <!DOCTYPE html>
    <html>
        <head id="head">
            <meta charset="UTF-8">
            <title></title>
            <!--第一种,需要在后端提供写js的回调函数,jsonp方式-->
            <!--<script>
                function callbackFunction(result){
                    alert(result.data[0].deptName);
                }
            </script>
            <script type="text/javascript" src="http://192.168.192.130/test.php?jsoncallback=callbackFunction"></script>-->
            
            <!--第二种,在后端添加,允许跨域请求的请求头-->
            <!--// 允许 ityangs.net 发起的跨域请求
                //header("Access-Control-Allow-Origin: ityangs.net"); 
                // 允许 ityangs.net 发起的跨域请求
                header("Access-Control-Allow-Origin: *");-->
                
            <!--第三种,由后端抓取要跨域的请求的内容,然后页面访问本地后端-->
            
        </head>
        <body>
            <script>
                var xmlhttp;
                if (window.XMLHttpRequest){
                    // IE7+, Firefox, Chrome, Opera, Safari 浏览器执行的代码
                    xmlhttp = new XMLHttpRequest();
                 }else{    
                    //IE6, IE5 浏览器执行的代码
                    xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
                }
                
                xmlhttp.onreadystatechange=function(){
                    if (xmlhttp.readyState==4 && xmlhttp.status==200){
                        var obj = JSON.parse(xmlhttp.responseText);
                        alert(xmlhttp.responseText);
                    }
                }
                //GET方式访问,true为异步,false为异步
                xmlhttp.open("GET","http://192.168.192.130/test2.php",false);
                xmlhttp.send();
            </script>
        
        </body>
        
    </html>
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  • 原文地址:https://www.cnblogs.com/makalochen/p/10669586.html
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