是否图片文件

2017-01-25 17:11:17 访问(1414) 赞(0) 踩(0)


        /// <summary>
        /// 是否图片文件
        /// </summary>
        /// <param name="attach"></param>
        /// <returns></returns>
        public bool IsImageFile(string str)
        {
            if (str == null)
                return false;

            str = str.Trim();

            int idx = str.LastIndexOf('.');

            if (idx == -1)
                return false;

            string strEx = str.Substring(idx + 1);

            strEx = strEx.Trim().ToLower();

            switch (strEx)
            {
                case "jpg":
                    return true;
                case "png":
                    return true;
                case "bmp":
                    return true;
                case "gif":
                    return true;
                default:
                    return false;
            }

        }