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。

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