最近在研究ajax图片上传，图片异步上传，更新，留作参考。
直接上源码吧：
js源码：
/// <reference path="jquery-1.8.3.js" /> /// <reference path="ajaxForm/jquery.form.js" /> /*! * jQuery upload * 用于上传单个文件，上传成功后,返回文件路径。 * 本插件依赖jQuery，jquery.form 请在使用时引入依赖的文件 * * Date: 2014/4/23 */ /* <div> <input type="hidden" value="/uploads/2014/04/23/635338686611432716.jpg" /> <div></div> <span> <input type="file" /> </span> <input type="button" value="上传" /> </div> <div> <input type="hidden" value="/uploads/2014/04/23/635338686611432716.jpg" /> <div></div> <span> <input type="file" /> </span> <input type="button" value="上传" /> </div>
js:
$(document).ready(function () { //$(".upload").upload({ // uploadData: { id: "12233" }, // successFn: function (response, statusText, xhr, $this) { // alert(response.Data.RelativePath) // }, // deleteData: { id: function () { return "asdfasdf" } } //}); $(".upload").upload({ uploadData: { id: "12233" }, successFn: "success", //可以是字符串 deleteData: { id: function () { return "asdfasdf" } } }); }); //上传成功后执行该函数 function success(response, statusText, xhr, $this) { //比如插入编辑器 alert(response.Data.RelativePath + $this.attr("value")) } */ (function ($) { $.extend($.fn, { upload: function (settings) { var options = $.extend({ fileType: "gif|jpg|jpeg|png|bmp", //允许的文件格式 uploadUrl: "/ajax/handler.ashx?action=uploadfile", //上传URL地址 deleteUrl: "/ajax/handler.ashx?action=deletefile", //删除URL地址 width: "", //图片显示的宽度 height: 100, //图片显示的高度 imgSelector: ".imgdiv", //图片选择器 uploadData: {}, //上传时需要附加的参数 deleteData: {}, //删除时需要附加的参数 deleteFn: function ($parent, showMessage) { //删除图片的方法(默认方法使用POST提交) methods.deleteImage($parent, showMessage); }, beforeSubmitFn: "beforeUpload", //上传前执行的方法 原型 beforeSubmit(arr, $form, options); successFn: "uploadSuccess", //上传成功后执行的方法 uploadSuccess(response, statusText, xhr, $this) errorFn: "uploadError" //上传失败后执行的方法 }, settings); //上传准备函数 var methods = { //验证文件格式 checkFile: function (filename) { var pos = filename.lastIndexOf("."); var str = filename.substring(pos, filename.length); var str1 = str.toLowerCase(); if (typeof options.fileType !== 'string') { options.fileType = "gif|jpg|jpeg|png|bmp"; } var re = new RegExp("\.(" + options.fileType + ")$"); return re.test(str1); }, //创建表单 createForm: function () { var $form = document.createElement("form"); $form.action = options.uploadUrl; $form.method = "post"; $form.enctype = "multipart/form-data"; $form.style.display = "none"; //将表单加当document上， document.body.appendChild($form); //创建表单后一定要加上这句否则得到的form不能上传。document后要加上body,否则火狐下不行。 return $($form); }, //创建图片 createImage: function () { //不能用 new Image() 来创建图片，否则ie下不能改变img 的宽高 var img = $(document.createElement("img")); img.attr({ "title": "双击图片可删除图片！" }); if (options.width !== "") { img.attr({ "width": options.width }); } if (options.height !== "") { img.attr({ "height": options.height }); } return img; }, showImage: function (filePath, $parent) { var $img = methods.createImage(); $parent.find(options.imgSelector).find("img").remove(); //要先append再给img赋值，否则在ie下不能缩小宽度。 $img.appendTo($parent.find(options.imgSelector)); $img.attr("src", filePath); this.bindDelete($parent); }, bindDelete: function ($parent) { $parent.find(options.imgSelector).find("img").bind("dblclick", function () { options.deleteFn($parent, true); }); }, deleteImage: function ($parent, showMessage) { var $fileInput = $parent.find("input:hidden"); if ($fileInput.val() !== "") { var data = $.extend(options.deleteData, { filePath: $fileInput.val(), t: Math.random() }); $.post(options.deleteUrl, data, function (response) { if (showMessage) { alert(response.MessageContent) } if (response.MessageType == 1) { $fileInput.val(""); $parent.find(options.imgSelector).find("img").remove(); } }, "JSON"); } }, onload: function ($parent) { var hiddenInput = $parent.find("input:hidden"); if (typeof hiddenInput !== "undefined" && hiddenInput.val() !== "") { var img = methods.createImage(); if ($parent.find(options.imgSelector).find("img").length > 0) { $parent.find(options.imgSelector).find("img").remove(); } //要先append再给img赋值，否则在ie下不能缩小宽度。 img.appendTo($parent.find(options.imgSelector)); img.attr("src", hiddenInput.val()); methods.bindDelete($parent); } } }; //上传主函数 this.each(function () { var $this = $(this); methods.onload($this.parent()); $this.bind("click", function () { var $fileInput = $(this).parent().find("input:file"); var fileBox = $fileInput.parent(); if ($fileInput.val() === "") { alert("请选择要上传的图片！"); return false; } //验证图片 if (!methods.checkFile($fileInput.val())) { alert("文件格式不正确，只能上传格式为：" + options.fileType + "的文件。"); return false; } //若隐藏域中有图片，先删除图片 if ($fileInput.val() !== "") { options.deleteFn($this.parent(), false); //methods.deleteImage($this.parent(), false); } //创建表单 var $form = methods.createForm(); //把上传控件附加到表单 $fileInput.appendTo($form); fileBox.html("<img src=https://www.jb51.net/article/\"/admin/styles/images/loading.gif\" /> 正在上传... "); $this.attr("disabled", true); //构建ajaxSubmit参数 var data = {}; data.data = options.uploadData; data.type = "POST"; data.dataType = "JSON"; //上传前 data.beforeSubmit = function (arr, $form, options) { var beforeSubmitFn; try { beforeSubmitFn = eval(options.beforeSubmitFn) } catch (err) { }; if (beforeSubmitFn) { var $result = beforeSubmitFn(arr, $form, options); if (typeof ($result) == "boolean") return $result; } }; //上传失败 data.error = function (response, statusText, xhr, $form) { var errorFn; try { errorFn = eval(options.errorFn) } catch (err) { }; if (errorFn) { errorFn(response.responseText, statusText, xhr, $this); } }; //上传成功 data.success = function (response, statusText, xhr, $form) { //response = eval("(" + response + ")"); if (response.MessageType == 1) { methods.showImage(response.Data.RelativePath, $this.parent()); $this.parent().find("input:hidden").val(response.Data.RelativePath); var successFn; try { successFn = eval(options.successFn) } catch (err) { }; if (successFn) { $.ajaxSetup({ cache: false });//这个不能少，否则ie下会提示下载 successFn(response, statusText, xhr, $this); } } else { alert(response.MessageContent); } $this.attr("disabled", false); fileBox.html("<input type=https://www.jb51.net/article/\"file\" name=https://www.jb51.net/article/\"file\" />"); $form.remove(); }; try { //开始ajax提交表单 $form.ajaxSubmit(data); } catch (e) { alert(e.message); } }); }); } }); })(jQuery)
html代码：