jquery+php實現ajax單個上傳

HTML部分 <script type="text/javascript" src="jquery.min.js"></script> <script type="text/javascript" src="jquery.form.js"></script>   <div class="btn">      <span>添加附件</span>      <input id="fileupload" type="file" name="mypic"> </div> <div class="progress">     <span class="bar"></span><span class="percent">0%</span > </div> <div class="files"></div> <div id="showimg"></div> CSS部分 .btn{position: relative;overflow: hidden;margin-right: 4px;display:inline-block; *display:inline;padding:4px 10px 4px;font-size:14px;line-height:18px; *line-height:20px;color:#fff; text-align:center;vertical-align:middle;cursor:pointer;background:#5bb75b; border:1px solid #cccccc;border-color:#e6e6e6 #e6e6e6 #bfbfbf; border-bottom-color:#b3b3b3;-webkit-border-radius:4px; -moz-border-radius:4px;border-radius:4px;} .btn input{position: absolute;top: 0; right: 0;margin: 0;border:solid transparent; opacity: 0;filter:alpha(opacity=0); cursor: pointer;} .progress{position:relative; margin-left:100px; margin-top:-24px;   width:200px;padding: 1px; border-radius:3px; display:none} .bar {background-color: green; display:block; width:0%; height:20px;   border-radius:3px; } .percent{position:absolute; height:20px; display:inline-block;   top:3px; left:2%; color:#fff } .files{height:22px; line-height:22px; margin:10px 0} .delimg{margin-left:20px; color:#090; cursor:pointer} js部分 $(function () {     var bar = $('.bar');     var percent = $('.percent');     var showimg = $('#showimg');     var progress = $(".progress");     var files = $(".files");     var btn = $(".btn span");     $("#fileupload").wrap("<form id='myupload' action='action.php'       method='post' enctype='multipart/form-data'></form>");     $("#fileupload").change(function(){ //選擇文件         $("#myupload").ajaxSubmit({             dataType:  'json', //數據格式爲json             beforeSend: function() { //開始上傳                 showimg.empty(); //清空顯示的圖片                 progress.show(); //顯示進度條                 var percentVal = '0%'; //開始進度爲0%                 bar.width(percentVal); //進度條的寬度                 percent.html(percentVal); //顯示進度爲0%                 btn.html("上傳中..."); //上傳按鈕顯示上傳中             },             uploadProgress: function(event, position, total, percentComplete) {                 var percentVal = percentComplete + '%'; //得到進度                 bar.width(percentVal); //上傳進度條寬度變寬                 percent.html(percentVal); //顯示上傳進度百分比             },             success: function(data) { //成功                 //得到後臺返回的json數據，顯示文件名，大小，以及刪除按鈕                 files.html("<b>"+data.name+"("+data.size+"k)</b>                   <span class='delimg' rel='"+data.pic+"'>刪除</span>");                 //顯示上傳後的圖片                 var img = "http://demo.helloweba.com/upload/files/"+data.pic;                 showimg.html("<img src='"+img+"'>");                 btn.html("添加附件"); //上傳按鈕還原             },             error:function(xhr){ //上傳失敗                 btn.html("上傳失敗");                 bar.width('0');                 files.html(xhr.responseText); //返回失敗信息             }         });     });     ... }); //接下來，文件上傳完成，若是用戶想刪除上傳的文件，能夠寫個ajax post請求來完成刪除操做。 $(function () {     ...接上面的代碼     $(".delimg").live('click',function(){         var pic = $(this).attr("rel");         $.post("action.php?act=delimg",{imagename:pic},function(msg){             if(msg==1){                 files.html("刪除成功.");                 showimg.empty(); //清空圖片                 progress.hide(); //隱藏進度條             }else{                 alert(msg);             }         });     }); }); PHP部分 action.php中須要處理圖片上傳以及刪除圖片。圖片上傳時須要驗證格式和大小，而後經過move_uploaded_file()方法上傳圖片，最後返回json格式的數據。刪除圖片時使用unlink()便可完成刪除操做。 $action = $_GET['act']; if($action=='delimg'){ //刪除圖片     $filename = $_POST['imagename'];     if(!empty($filename)){         unlink('files/'.$filename);         echo '1';     }else{         echo '刪除失敗.';     } }else{ //上傳圖片     $picname = $_FILES['mypic']['name'];     $picsize = $_FILES['mypic']['size'];     if ($picname != "") {         if ($picsize > 512000) { //限制上傳大小             echo '圖片大小不能超過500k';             exit;         }         $type = strstr($picname, '.'); //限制上傳格式         if ($type != ".gif" && $type != ".jpg") {             echo '圖片格式不對！';             exit;         }         $rand = rand(100, 999);         $pics = date("YmdHis") . $rand . $type; //命名圖片名稱         //上傳路徑         $pic_path = "files/". $pics;         move_uploaded_file($_FILES['mypic']['tmp_name'], $pic_path);     }     $size = round($picsize/1024,2); //轉換成kb     $arr = array(         'name'=>$picname,         'pic'=>$pics,         'size'=>$size     );     echo json_encode($arr); //輸出json數據 } 本文藉助了jquery form插件來完成單文