ajax之---上传文件

    “伪”ajax向后台提交文件
    
    <iframe style="display: none" id="iframe1" name="ifra1"></iframe>
    <form id="fm1" action="/ajax1.html" method="POST" enctype="multipart/form-data" target="ifra1">
        <input type="text" name="k1" />
        <input type="text" name="k2" />
        <input type="file" name="k3" />
        <a onclick="AjaxSubmit8()">提交</a>
    </form>
    <script>
            function AjaxSubmit8() {
            document.getElementById('iframe1').onload = reloadIframe1;
            document.getElementById('fm1').submit();
        }
        function reloadIframe1() {
            var content = this.contentWindow.document.body.innerHTML;
            var obj = JSON.parse(content);
            console.log(obj);
        }
    </script>
    
    jquery ajax向后台提交文件
    
    <input type="file" id="img" />
    <a class="btn" onclick="AjaxSubmit6();">上传</a>
    <script>
            function AjaxSubmit6() {
            //document.getElementById('img')[0]
            var data = new FormData();
            data.append('k1','v1');
            data.append('k2','v2');
            data.append('k3',document.getElementById('img').files[0]);

            $.ajax({
                url: '/ajax1.html',
                type: 'POST',
                data:data,
                success:function (arg) {
                    console.log(arg)
                },
                 processData: false,  // tell jQuery not to process the data
                 contentType: false  // tell jQuery not to set contentType

            })
        }
    </script>

    原生ajax向后台提交文件
    
    <input type="file" id="img" />
    <a class="btn" onclick="AjaxSubmit6();">上传</a>
    <script>
            function AjaxSubmit7() {
            var data = new FormData();
            data.append('k1','v1');
            data.append('k2','v2');
            data.append('k3',document.getElementById('img').files[0]);

            var xhr = new XMLHttpRequest();
            xhr.onreadystatechange = function () {
                if(xhr.readyState == 4){
                    // 接收完毕服务器返回的数据
                    console.log(xhr.responseText);

                }
            };
            xhr.open('POST','/ajax1.html');
            xhr.send(data);
        }
    </script>