asp.net 替换字符串,正则替换字符串,不区分大小写替换字符串,替换html标签

using System;
using System.Text;
using System.Text.RegularExpressions;//这个一定要加

namespace EC
{
/// <summary>
/// 替换字符串
/// </summary>
public class StringRepStrs
{

 

public StringRepStrs ()
{
}

#region 普通替换字符串

/// <summary>
/// 普通替换字符串

/// </summary>
/// <param name="src">源字符串</param>
/// <param name="pattern">要匹配的正则表达式模式</param>
/// <param name="replacement">替换字符串</param>
/// <returns>已修改的字符串</returns>
public static string Replace (string src, string pattern, string replacement)
{
   return Replace(src, pattern, replacement, RegexOptions.None);
}

#endregion

#region 正则替换字符串

/// <summary>
/// 正则替换字符串

/// </summary>
/// <param name="src">要修改的字符串</param>
/// <param name="pattern">要匹配的正则表达式模式</param>
/// <param name="replacement">替换字符串</param>
/// <param name="options">匹配模式</param>
/// <returns>已修改的字符串</returns>
public static string Replace (string src, string pattern, string replacement, RegexOptions options)
{
   Regex regex = new Regex(pattern, options|RegexOptions.Compiled);

   return regex.Replace(src, replacement);
}

#endregion

#region 不区分大小写替换字符串

/// <summary>
/// 不区分大小写替换字符串

/// </summary>
/// <param name="src">源字符串</param>
/// <param name="pattern">要匹配的正则表达式模式</param>
/// <param name="replacement">替换字符串</param>
/// <returns>已修改的字符串</returns>
public static string ReplaceIgnoreCase (string src, string pattern, string replacement)
{
   return Replace(src, pattern, replacement, RegexOptions.IgnoreCase);
}

#endregion

 

/// <summary>
/// 删除字符串中指定的内容
/// </summary>
/// <param name="src">要修改的字符串</param>
/// <param name="pattern">要删除的正则表达式模式</param>
/// <returns>已删除指定内容的字符串</returns>
public static string Drop (string src, string pattern)
{
   return Replace(src, pattern, "");
}

/// <summary>
/// 删除字符串中指定的内容,不区分大小写
/// </summary>
/// <param name="src">要修改的字符串</param>
/// <param name="pattern">要删除的正则表达式模式</param>
/// <returns>已删除指定内容的字符串</returns>
public static string DropIgnoreCase (string src, string pattern)
{
   return ReplaceIgnoreCase(src, pattern, "");
}

/// <summary>
/// 替换字符串到数据库可输入模式
/// </summary>
/// <param name="src">待插入数据库的字符串</param>
/// <returns>可插入数据库的字符串</returns>
public static string ToSQL (string src)
{
   if (src == null)
   {
    return null;
   }
   return Replace(src, "", "");
}

/// <summary>
/// 去掉html内容中的指定的html标签
/// </summary>
/// <param name="content">html内容</param>
/// <param name="tagName">html标签</param>
/// <returns>去掉标签的内容</returns>
public static string DropHtmlTag (string content, string tagName)
{
   //去掉<tagname>和</tagname>
   return DropIgnoreCase(content, "<[/]{0,1}" + tagName + "[^\\>]*\\>");
}

/// <summary>
/// 去掉html内容中全部标签
/// </summary>
/// <param name="content">html内容</param>
/// <returns>去掉html标签的内容</returns>
public static string DropHtmlTag (string content)
{
   //去掉<*>
   return Drop(content, "<[^\\>]*>");
}

    /// <summary>
/// 判断一个数据是不是数字
/// </summary>
/// <param name="inputData">字符串</param>
/// <returns>结果</returns>
public static bool IsNumeric(string inputData)
{
   Regex _isNumber = new Regex(@"^\d+{$article$}quot;);
   Match m = _isNumber.Match(inputData);
   return m.Success;
}

/// <summary>
/// 转换html标签为web页可见内容
/// </summary>
/// <param name="src"></param>
/// <returns></returns>
public static string EscapeHtml (string src)
{
   if (src == null)
   {
    return null;
   }
   string s = src;
   s = Replace(s, ">", "&gt;");
   s = Replace(s, "<", "&lt;");
   return s;
}

/// <summary>
/// 将字符串格式化成HTML代码
/// </summary>
/// <param name="str">要格式化的字符串</param>
/// <returns>格式化后的字符串</returns>
public static String ToHtml(string str)
{
   if (str == null || str.Equals(""))
   {
    return str;
   }
           
   StringBuilder sb= new StringBuilder(str);
   sb.Replace("&", "&amp;");
   sb.Replace("<", "&lt;");
   sb.Replace(">", "&gt;");
   sb.Replace("\r\n", "<br>");
   sb.Replace("\n", "<br>");
   sb.Replace("\t", " ");
   sb.Replace(" ", "&nbsp;");
   return sb.ToString();
}

/// <summary>
/// 将HTML代码转化成文本格式
/// </summary>
/// <param name="str">要格式化的字符串</param>
/// <returns>格式化后的字符串</returns>
public static String ToTxt(String str)
{
   if (str == null || str.Equals(""))
   {
    return str;
   }
           
   StringBuilder sb= new StringBuilder(str);
   sb.Replace("&nbsp;", " ");
   sb.Replace("<br>", "\r\n");
   sb.Replace("&lt;", "<");
   sb.Replace("&gt;", ">");
   sb.Replace("&amp;", "&");
   return sb.ToString();
}
}
}