ASP.NET過濾HTML標(biāo)簽只保留換行與空格的方法

字號(hào):


    本文實(shí)例講述了ASP.NET過濾HTML標(biāo)簽只保留換行與空格的方法。分享給大家供大家參考。具體分析如下:
    自己從網(wǎng)上找了一個(gè)過濾HTML標(biāo)簽的方法,我也不知道誰的才是原創(chuàng)的,反正很多都一樣。我把那方法復(fù)制下來,代碼如下:
    復(fù)制代碼 代碼如下:/// <summary>
    /// 去除HTML標(biāo)記
    /// </summary>
    /// <param name="NoHTML">包括HTML的源碼 </param>
    /// <returns>已經(jīng)去除后的文字</returns>
    public static string NoHTML(string Htmlstring)
    {
    //刪除腳本
    Htmlstring = Regex.Replace(Htmlstring, @"<script[^>]*?>.*?</script>", "",
    RegexOptions.IgnoreCase);
    //刪除HTML
    Htmlstring = Regex.Replace(Htmlstring, @"<(.[^>]*)>", "",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"([\r\n])[\s]+", "",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"-->", "", RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"<!--.*", "", RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(quot|#34);", "\"",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(amp|#38);", "&",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(lt|#60);", "<",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(gt|#62);", ">",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(nbsp|#160);", " ",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(iexcl|#161);", "\xa1",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(cent|#162);", "\xa2",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(pound|#163);", "\xa3",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(copy|#169);", "\xa9",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&#(\d+);", "",
    RegexOptions.IgnoreCase);
    Htmlstring.Replace("<", "");
    Htmlstring.Replace(">", "");
    Htmlstring.Replace("\r\n", "");
    Htmlstring = HttpContext.Current.Server.HtmlEncode(Htmlstring).Trim();
    return Htmlstring;
    }
    以上代碼是從網(wǎng)上直接復(fù)制過來的,這個(gè)確實(shí)能過濾掉所有的HTML標(biāo)簽,但是這個(gè)不是我想要的,這個(gè)過濾得太干凈了,我如果用textarea輸入框的話,我是要保留空格跟換行的。
    然后我就自己改了一下這個(gè)方法,textarea的換行是\n,所以我得把這些標(biāo)簽重新匹配替換成<br>,這樣的話從數(shù)據(jù)庫中讀取到頁面時(shí),就能正確的換行了,把空格替換成HTML的空格符,大功告成。
    復(fù)制代碼 代碼如下:/// <summary>
    /// 去除HTML標(biāo)記(保留br跟\r\n)
    /// </summary>
    /// <param name="NoHTML">包括HTML的源碼 </param>
    /// <returns>已經(jīng)去除后的文字</returns>
    public static string NewNoHTML(string Htmlstring)
    {
    //Htmlstring.Replace("", "%r%n").Replace("<br>","%br%").Replace("<br/>","%br&%").Replace("");
    //刪除腳本
    Htmlstring = Regex.Replace(Htmlstring, @"<script[^>]*?>.*?</script>", "",
    RegexOptions.IgnoreCase);
    //刪除HTML
    Htmlstring = Regex.Replace(Htmlstring, @"<(.[^>]*)>", "",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"-->", "", RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"<!--.*", "", RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(quot|#34);", "\"",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(amp|#38);", "&",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(lt|#60);", "<",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(gt|#62);", ">",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(nbsp|#160);", " ",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(iexcl|#161);", "\xa1",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(cent|#162);", "\xa2",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(pound|#163);", "\xa3",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&(copy|#169);", "\xa9",
    RegexOptions.IgnoreCase);
    Htmlstring = Regex.Replace(Htmlstring, @"&#(\d+);", "",
    RegexOptions.IgnoreCase);
    Htmlstring.Replace("<", "");
    Htmlstring.Replace(">", "");
    //Htmlstring.Replace("\r\n", "");
    Htmlstring = HttpContext.Current.Server.HtmlEncode(Htmlstring);
    Htmlstring = Regex.Replace(Htmlstring, @"((\r\n))", "<br>");
    Htmlstring = Regex.Replace(Htmlstring, @"(\r|\n)", "<br>");
    Htmlstring = Regex.Replace(Htmlstring, @"(\s)", " ");
    return Htmlstring;
    }
    這個(gè)過濾可以用于讓用戶輸入發(fā)布內(nèi)容時(shí)的過濾。
    希望本文所述對(duì)大家的asp.net程序設(shè)計(jì)有所幫助。