1.先使用ajaxfileupload插件做异步上传。这个地方我本来想做个上传进度的效果，但技术有限失败了。上传按钮我还做了一个文件大小的限制，但是由于浏览器兼容性的问题，不完美在IE6--IE9之间还有很多问题需要解决

getFileSize函数是用于判断文件大小的函数

复制代码 代码如下:

function getFileSize(fileName) {
                var byteSize = 0;
                //console.log($("#" + fileName).val());
                if($("#" + fileName)[0].files) {
                    var byteSize  = $("#" + fileName)[0].files[0].size;
                }else {
    //此处由于有浏览器兼容问题 还没完成大小判断的逻辑
                }
                //alert(byteSize);
                byteSize = Math.ceil(byteSize / 1024) //KB
                return byteSize;//KB
            }

2.按钮上传事件绑定

复制代码 代码如下:

$("#btnUpload").click(function () {
                var allowImgageType = ['jpg', 'jpeg', 'png', 'gif'];
                var file = $("#file1").val();
                //获取大小
                var byteSize = getFileSize('file1');
                //获取后缀
                if (file.length > 0) {
                    if(byteSize > 2048) {
                        alert("上传的附件文件不能超过2M");
                        return;
                    }
                    var pos = file.lastIndexOf(".");
                    //截取点之后的字符串
                    var ext = file.substring(pos + 1).toLowerCase();
                    //console.log(ext);
                    if($.inArray(ext, allowImgageType) != -1) {
                        ajaxFileUpload();
                    }else {
                        alert("请选择jpg,jpeg,png,gif类型的图片");
                    }
                }
                else {
                    alert("请选择jpg,jpeg,png,gif类型的图片");
                }
            });

3.在上传成功后返回图片路径，并初始化图片裁剪。图片裁剪就直接用ajax请求到php

复制代码 代码如下:

function ajaxFileUpload() {
                $.ajaxFileUpload({
                    url: 'action.php', //用于文件上传的服务器端请求地址
                    secureuri: false, //一般设置为false
                    fileElementId: 'file1', //文件上传空间的id属性 
                    dataType: 'json', //返回值类型 一般设置为json
                    success: function (data, status)  //服务器成功响应处理函数
                    {
                        //var json = eval('(' + data + ')');
                        //alert(data);
                        $("#picture_original>img").attr({src: data.src, width: data.width, height: data.height});
                        $('#imgsrc').val(data.path);
                        //alert(data.msg);

                        //同时启动裁剪操作，触发裁剪框显示，让用户选择图片区域
                        var cutter = new jQuery.UtrialAvatarCutter({
                                //主图片所在容器ID
                                content : "picture_original",
                                //缩略图配置,ID:所在容器ID;width,height:缩略图大小
                                purviews : [{id:"picture_200",width:200,height:200},{id:"picture_50",width:50,height:50},{id:"picture_30",width:30,height:30}],
                                //选择器默认大小
                                selector : {width:200,height:200},
                                showCoords : function(c) { //当裁剪框变动时，将左上角相对图片的X坐标与Y坐标 宽度以及高度
                                    $("#x1").val(c.x);
                                    $("#y1").val(c.y);
                                    $("#cw").val(c.w);
                                    $("#ch").val(c.h);
                                },
                                cropattrs : {boxWidth: 500, boxHeight: 500}
                            }
                        );
                        cutter.reload(data.src);
                        $('#div_avatar').show();
                    },
                    error: function (data, status, e)//服务器响应失败处理函数
                    {
                        alert(e);
                    }
                })
                return false;
            }

            $('#btnCrop').click(function() {
                $.getJSON('action2.php', {x: $('#x1').val(), y: $('#y1').val(), w: $('#cw').val(), h: $('#ch').val(), src: $('#imgsrc').val()}, function(data) {
                    alert(data.msg);
                });
                return false;
            });

4.HTML文件代码如下

复制代码 代码如下: