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PHP+Ajax,该怎么处理

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Jun 13, 2016 pm 12:24 PM

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PHP+Ajax

<br /><script><br />            function ajaxFileUpload() {<br />                $.ajax({<br />                    url: 'a.php',<br />                    type: 'post',<br />                    dateType: 'json',<br />                    data: {upfile:$("#ss").val()},<br />                    success: function (result) {<br />                       alert("success");<br />                    },<br />                    error: function (result) {<br />                        alert("error");<br />                    }<br />                });<br />            }<br />        </script><br /> <body>  <br />        <form enctype="multipart/form-data" action="a.php" method="post" name="upform" id="upform"><br />          上传文件:  <br />          <input name="upfile" type="file" onchange="ajaxFileUpload()" id="ss"><br />          <input type="submit" value="上传"><br><br />        </form><br />    </body>  <br /><br />a.php<br /> if (!is_uploaded_file($_FILES["upfile"]["tmp_name"]))<br />       //如果我直间提交表单  $_FILES是有值的  (Array ( [upfile] => Array ( [name] => 1.jpg [type] => image/jpeg [tmp_name] => C:\Windows\phpC106.tmp [error] => 0 [size] => 7108 ) ) )<br />      //但我用ajax提交时,  $_FILES是没有值,这个要怎么解决?<br />    {<br />        echo "图片不存在!";<br />        exit;<br />    }<br /><br />

------解决思路----------------------
你这样做是行不通的。异步上传文件我知道的有三种方法，第一种HTML5 FILE API方法,可以直接读取文件内容。第二种通过Flash插件来上传，所有工作交由Flash来完成，比如SwfUpload。第三种就是纯JavaScript完成异步上传。下面我们来介绍第三种方法。要借用iframe。参考代码:

<br /><div class="file_upload_control"><br />  <form class="file_control_form" enctype="multipart/form-data" action="ajax/upload.image.php"<br />  target="iframe_2C4B15FAD29E311E3CBACEADE9EE8F4A" method="post"><br />    <input type="hidden" name="APC_UPLOAD_PROGRESS" class="apc_id" value="2C4B15FAD29E311E3CBACEADE9EE8F4A"<br />    /><br />    <input type="hidden" value="2C4B15FAD29E311E3CBACEADE9EE8F4A" name="file_control_guid"<br />    /><br />    <input type="hidden" value="module_menu" name="file_control_module" /><br />    <!-----2C4B15FAD29E311E3CBACEADE9EE8F4A 这个是GUID-----><br />    可以同时上传多个文件，用GUID进行区分<br />    <input name="2C4B15FAD29E311E3CBACEADE9EE8F4A" class="file_control" type="file"<br />    /><br />    <div class="file_preview"> <!---- 图片上传前预览-----><br />      <img  class="file_preview_img lazy"  src="/static/imghwm/default1.png"  data-src="images/upload_delete.png"   / alt="PHP+Ajax,该怎么处理" ><br />    </div><br />    <div > <!----- 文件验证错误提示----><br />      <div ><br />      </div><br />    </div><br />    <div > <!---- 文件上传进度条-----><br />      <div ><br />        <div ><br />        </div><br />      </div><br />    </div><br />    <div > <!----- 上传成功后的Logo标志------><br />      <div ><br />      </div><br />    </div><br />    <div >    <!----- 上传成功后 删除按钮 -----><br />      <img  class="file_preview_img lazy"  src="/static/imghwm/default1.png"  data-src="images/upload_delete.png"   / alt="PHP+Ajax,该怎么处理" ><br />    </div><br /></div><br /></form><br /><!---- iframe 是异步提交的关键, 注意iframe name属性要和form target中的值完全一致 -----><br /><iframe   style="max-width:90%" src="" id="iframe_2C4B15FAD29E311E3CBACEADE9EE8F4A"<br />name="iframe_2C4B15FAD29E311E3CBACEADE9EE8F4A"><br /></iframe><br /></div><br />

<br />$(document).on('change','.file_upload_control .file_control',function(){<br />    //第一步获取file值<br />    var file = $(this).val();<br />   //第二步上传前校验<br />    if(!CheckFile(file)){<br />        ClearFileControl($(this)); //清空文件的内容<br />        return;<br />    }<br />     //第三步，如果上传的是图片，在本地进行上传前的预览<br />     PreviewImg($file);<br />     //第四步，提交上传<br />     $(this).parent().submit(); //提交form<br />     //第五步，如果上传的文件比较大(100M),查询进度，记得配置服务器支持大文件，否则上传不会成功！<br />     var file_guid = $(this).siblings('.file_control_guid').val();<br />     //第六步，查询文件上传进度，需要服务端程序进行配合，我这里举例的是PHP代码，需要使用PHP_APC.dll第三方插件协助       完成<br />     setTimeout('GetUploadProgress("'+file_guid+'"),500);<br />});<br />

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