ASP.NET MVC+EntityFramework图片头像上传功能实现

  <div class="form-group">
            @Html.LabelFor(model => model.img, "头像：", htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @*@Html.EditorFor(model => model.img, new { htmlAttributes = new { @class = "form-control" } })*@
                <input class="width-main input" type="file" datatype="*" id="pic" name="pic" value="" accept="image/*" onchange="upload(event)">
                <input type="hidden" name="img" id="img" value="" />
                <div id="showImg"></div>
            </div>
        </div>

<script>
    //实现异步上传
    function upload(event) {
        var imgPath = $("#pic").val();
        console.log(imgPath);
        //判断上传文件的后缀名
        var strExtension = imgPath.substr(imgPath.lastIndexOf('.') + 1);
        if (strExtension != 'jpg' && strExtension != 'gif' && strExtension != 'png' && strExtension != 'bmp') {
            alert("请选择图片文件");
            return;
        }
        //实现文件上传操作
        if (event.target.files[0].type.search('image') !== -1) {
            //实现文件图片的上传
            var formData = new FormData($("#myForm")[0]);//用于创建一个文件流对象
            //formData.append('pic', $("#img")[0]); //添加文件流 （流名称，流）
            //console.log(formData);
            $.ajax({
                url: "/Upload/file",
                type: "post",
                cache: false,
                processData: false,
                contentType: false,
                data: formData,
                success: function (res) {
                    console.log(res);
                    if (res.trim() == "209") {
                        alert("请选择图片！");
                        return;
                    }
                    if (res.trim() == "300") {
                        alert("上传的图片不能为空图片！");
                        return;
                    }
                    if (res.trim() == "400") {
                        alert("上传的图片失败！");
                        return;
                    }
                    //alert("上传成功！");
                    $("#showImg").html("<img src='" + res + "' width='50' height='50' /><p style='color:red;'>上传成功！</p>");
                    //设置上传的图片地址
                    var res = res.trim(); //去除图片的前后空白字符
                    $("#img").val(res);
                },
                error: function (res) {
                    alert("上传异常！");
                }
            });
        } else {
            alert('只支持上传图片');
        }
    }
</script>

  //图片上传
        [HttpPost]
        public ActionResult file(HttpPostedFileBase pic)
        {
            try
            {
                if (pic != null)
                {
                    if (pic.ContentLength == 0)
                    {
                        return Content("209"); //获取上传的图片
                    }
                    else
                    {
                        //判断文件的后缀名，是否符合条件
                        string backFix = Path.GetExtension(pic.FileName);
                        if (backFix != ".gif" && backFix != ".png" && backFix != ".jpg" && backFix != ".jpeg")
                        {
                            return Content("210"); //格式不对
                        }
                        string fileName = DateTime.Now.ToString("MMddHHmmss") + backFix;
                        string strPath = Server.MapPath("~/Content/pic/" + fileName);
                        pic.SaveAs(strPath);
                        //返回路径
                        return Content("/Content/pic/" + fileName);
                    }
                }
                else
                {
                    return Content("300"); //图片不能为空
                }
            }
            catch (Exception )
            {
                return Content("400"); //上传失败
            }
        }