public static string noHtml(string str)

        {

            if (str != null)

            {

                str = Regex.Replace(str, @"<script[^>]*>[\s\S]*?</script>", "", RegexOptions.IgnoreCase);//删除脚本

                str = Regex.Replace(str, @"(<style)+[^<>]*>[^\0]*(<\/style>)+", "", RegexOptions.IgnoreCase);//删除样式

                str = Regex.Replace(str, @"<object.*?/object>", "", RegexOptions.IgnoreCase);//删除object

                str = Regex.Replace(str, @"<!--.*", "", RegexOptions.IgnoreCase);//删除开始注释

                str = Regex.Replace(str, @"-->", "", RegexOptions.IgnoreCase);//删除结尾注释

                //str = Regex.Replace(str, @"<\/*[^<>]*>", "", RegexOptions.IgnoreCase);//删除全部html

                //str = Regex.Replace(str, @"<(\/){0,1}div[^<>]*>", "", RegexOptions.IgnoreCase);//删除div

                //str = Regex.Replace(str, @"<(\/){0,1}a[^<>]*>", "", RegexOptions.IgnoreCase);//删除超链接

                //str = Regex.Replace(str, @"<(\/){0,1}font[^<>]*>", "", RegexOptions.IgnoreCase);//删除文字样式

                //str = Regex.Replace(str, @"(class=){1,}(""|\'){0,1}\S+(""|\'|>|\s){0,1}", "", RegexOptions.IgnoreCase);//删除class

                //str = Regex.Replace(str, @"(<iframe){1,}[^<>]*>[^\0]*(<\/iframe>){1,}", "", RegexOptions.IgnoreCase);//删除框架

                //str = Regex.Replace(str, @"(<script){1,}[^<>]*>[^\0]*(<\/script>){1,}", "", RegexOptions.IgnoreCase);//删除脚本

                str = Regex.Replace(str, @"<(.[^>]*)>", "", RegexOptions.IgnoreCase);//删除全部html

                str = Regex.Replace(str, @"([\r\n])[\s]+", "", RegexOptions.IgnoreCase);//删除换行

                str = Regex.Replace(str, @"&nbsp;&nbsp;", "　", RegexOptions.IgnoreCase);//替换空格

            }

            return str;

        }