C# ASP.NET 手写板并生成图片保存

@{
    Layout = null;
}


"zh-CN">"X-UA-Compatible" content="IE=edge,chrome=1" />
    "UTF-8">
    "description" content="overview & stats" />
    "viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0" />
    
"signature">
    
"text-align: center">
        "color: red">请按着鼠标写字签名。
    
    "button" value="保存" id="yes" />
    "button" value="下载" id="download" />
    "button" value="重写" id="reset" />
    
"someelement">"" id="images">

    public ActionResult UploadSignature2(string src_data)
        {
            Class1.Base64StrToImage(src_data, "C:\\Users\\45448\\Desktop\\1\\"+ DateTime.Now.ToString("yyyyMMddHHss") + ".png");
            return Json(1, JsonRequestBehavior.AllowGet);
        }


        /// 

        /// 将Base64字符串转换为图片并保存到本地
        /// 
        /// base64字符串
        /// 图片保存地址，如：/Content/Images/10000.png
        /// 
        public static bool Base64StrToImage(string base64Str, string savePath)
        {
            var ret = true;
            try
            {
                base64Str = base64Str.Replace("data:image/png;base64,", "").Replace("data:image/jgp;base64,", "")
                    .Replace("data:image/jpg;base64,", "").Replace("data:image/jpeg;base64,", ""); //将base64头部信息替换
                var bitmap = Base64StrToImage(base64Str);
                if (bitmap != null)
                {
                    //创建文件夹
                    var folderPath = savePath.Substring(0, savePath.LastIndexOf(‘\\‘));
                    ////FileHelper.CreateDir(folderPath);
                    if (!Directory.Exists(folderPath))
                    {
                        Directory.CreateDirectory(folderPath);
                    }
                    //图片后缀格式
                    var suffix = savePath.Substring(savePath.LastIndexOf(‘.‘) + 1,
                        savePath.Length - savePath.LastIndexOf(‘.‘) - 1).ToLower();
                    var suffixName = suffix == "png"
                        ? ImageFormat.Png
                        : suffix == "jpg" || suffix == "jpeg"
                            ? ImageFormat.Jpeg
                            : suffix == "bmp"
                                ? ImageFormat.Bmp
                                : suffix == "gif"
                                    ? ImageFormat.Gif
                                    : ImageFormat.Jpeg;

                    //这里复制一份对图像进行保存，否则会出现“GDI+ 中发生一般性错误”的错误提示
                    var bmpNew = new Bitmap(bitmap);
                    bmpNew.Save(savePath, suffixName);
                    bmpNew.Dispose();
                    bitmap.Dispose();
                }
                else
                {
                    ret = false;
                }
            }
            catch (Exception ex)
            {
                ret = false;
            }
            return ret;
   
        }