Asp.net判断图片存在的并获取图片

/// <summary>
        /// 判断本地、远程图片，取图片
        /// </summary>
        /// <param name="RecPic">要判断的图片路径</param>
        /// <returns></returns>
        public static string GetDefualCourseImgtUrl(string RecPic)
        {
            string resultPath = string.Empty;
            string m_ImgPath = UploadPathHelper.GetUploadPath();
            if (string.IsNullOrEmpty(RecPic) || (!IsExistRemoteImage(RecPic) && !File.Exists(PathHelper.ServerMapPath("~/"+m_ImgPath + RecPic))))
            {
           //获取默认图片的方法
                resultPath = GetDefaultImageUrl();
            }
            else
            {
                if(IsExistRemoteImage(RecPic))
                {
                    resultPath = RecPic;
                }
                else if(File.Exists(PathHelper.ServerMapPath("~/"+m_ImgPath + RecPic)))//<span style="font-family: Arial, Helvetica, sans-serif;">PathHelper.ServerMapPath自己封装获取绝对路径的方法</span>
                {
                    resultPath = m_ImgPath + RecPic;
                }
                else
                {
                   //获取默认图片的方法
                   resultPath = GetDefaultImageUrl(); 
                } 
            } 
            return resultPath; 
        } 
        /// <summary> 
        /// 远程判断图片是否存在 
        /// </summary> 
        /// <param name="curl"></param> 
        /// <returns></returns> 
        private static bool IsExistRemoteImage(string curl) 
        { 
             try 
             { 
                 HttpWebRequest request = (HttpWebRequest)WebRequest.Create(new Uri(curl)); 
                 ServicePointManager.Expect100Continue = false; 
                ((HttpWebResponse)request.GetResponse()).Close();</span>
                 return true;
             } 
             catch 
             { 
                 return false; 
             } 
        }