ASP.NET公共类库之HTML格式辅助类HtmlUtils.cs

/**********************************************
 * 类作用：   HTML格式辅助类
 * 作者：开优网络
 * http://www.kaiu.net
 ***********************************************/

using System;
using System.Collections.Generic;
using System.Text;
using System.Text.RegularExpressions;


namespace Svnhost.Common
{
    public class HtmlUtils
    {

        /// <summary>
        /// 替换回车换行符为html换行符
        /// </summary>
        public static string StrFormat(string str)
        {
            string str2;

            if (str == null)
            {
                str2 = "";
            }
            else
            {
                str = str.Replace("\r\n", "<br />");
                str = str.Replace("\n", "<br />");
                str2 = str;
            }
            return str2;
        }


        public static string GetRealIP()
        {
            string ip = Request.GetIP();

            return ip;
        }

        /// <summary>
        /// 改正sql语句中的转义字符
        /// </summary>
        public static string mashSQL(string str)
        {
            string str2;

            if (str == null)
            {
                str2 = "";
            }
            else
            {
                str = str.Replace("\'", "'");
                str2 = str;
            }
            return str2;
        }

        /// <summary>
        /// 替换sql语句中的有问题符号
        /// </summary>
        public static string ChkSQL(string str)
        {
            string str2;

            if (str == null)
            {
                str2 = "";
            }
            else
            {
                str = str.Replace("'", "''");
                str2 = str;
            }
            return str2;
        }

       
        /// <summary>
        /// 替换html字符
        /// </summary>
        public static string EncodeHtml(string strHtml)
        {
            if (strHtml != "")
            {
                strHtml = strHtml.Replace(",", "&def");
                strHtml = strHtml.Replace("'", "&dot");
                strHtml = strHtml.Replace(";", "&dec");
                return strHtml;
            }
            return "";
        }
     
       
        /// <summary>
        /// 为脚本替换特殊字符串
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public static string ReplaceStrToScript(string str)
        {
            str = str.Replace("\\", "\\\\");
            str = str.Replace("'", "\\'");
            str = str.Replace("\"", "\\\"");
            return str;
        }

           
        /// <summary>
        /// 移除Html标记
        /// </summary>
        /// <param name="content"></param>
        /// <returns></returns>
        public static string RemoveHtml(string content)
        {
            string regexstr = @"<[^>]*>";
            return Regex.Replace(content, regexstr, string.Empty, RegexOptions.IgnoreCase);
        }

        /// <summary>
        /// 过滤HTML中的不安全标签
        /// </summary>
        /// <param name="content"></param>
        /// <returns></returns>
        public static string RemoveUnsafeHtml(string content)
        {
            content = Regex.Replace(content, @"(\<|\s+)o([a-z]+\s?=)", "$1$2", RegexOptions.IgnoreCase);
            content = Regex.Replace(content, @"(script|frame|form|meta|behavior|style)([\s|:|>])+", "$1.$2", RegexOptions.IgnoreCase);
            return content;
        }

 
        /// <summary>
        /// 从HTML中获取文本,保留br,p,img
        /// </summary>
        /// <param name="HTML"></param>
        /// <returns></returns>
        public static string GetTextFromHTML(string HTML)
        {
            System.Text.RegularExpressions.Regex regEx = new System.Text.RegularExpressions.Regex(@"</?(?!br|/?p|img)[^>]*>", System.Text.RegularExpressions.RegexOptions.IgnoreCase);

            return regEx.Replace(HTML, "");
        }      

 
    }
}