C#简单的上传图片

//CSS代码
#upload {
    height: 25px;
}

#upload input {
    float: left;
    margin: 0 20px 0 0;
}

#upload img {
    width: 25px;
    height: 25px;
    float: left;
}

#preview {
    width: 300px;
    margin: 10px 0 0 0;
}

#preview img {
    width: 300px;
    height: 260px;
}

//HTML代码
<form id="form1" name="form" enctype="multipart/form-data" method="post">
　　<div id="upload">
    　　<input type="file" id="uploadImage" name="uploadImage" />
    </div>
    <div id="preview">
       <img id="previewImage" src="/images/20160229/f039a733-28af-4a25-897a-b243e4ad6d0f.jpg" />
    </div>
</form>

//js代码，主意下面两个引用都要
<script src="~/Scripts/jquery-1.8.2.js"></script>
<script src="~/Scripts/jquery.form.js"></script>
<script type="text/javascript">
    $(function () {
        $("#uploadImage").change(function () {
            $("#form1").ajaxSubmit({
                url: '@Url.Action("AddImage")',
                success: function (data) {
                    if (data != "上传失败") {
                        $("#previewImage").attr("src", '@Url.Content("/images")/' + data + '');
                    }
                    else {
                        alert("上传失败");
                    }
                }
            });
        });
    });
</script>

//C#代码
try
   {
　　　　var file = Request.Files[0];
       //图片保存的文件夹路径
       string path = Server.MapPath("~/images/");
       //每天上传的图片一个文件夹，如果不用每天创建文件夹folder就不需要
       string folder = DateTime.Now.ToString("yyyyMMdd");
       //如果文件夹不存在，则创建
       if (!Directory.Exists(path + folder))
       {
       　　Directory.CreateDirectory(path + folder);
       }
       //上传图片的扩展名
       string type = file.FileName.Substring(file.FileName.LastIndexOf('.'));
       //保存图片的文件名
       string saveName = Guid.NewGuid().ToString() + type;
       //保存图片
       file.SaveAs(path + folder + "/" + saveName);
       return Json(folder + "/" + saveName);
    }
    catch
    {
    　　return Json("上传失败");
    }