C#数据采集用到的几个方法

这两天在做数据采集,因此整理了下数据采集要用到的一些方法。因为我采集的数据比较简单,所以没有用到框架。比较有名的两个框架 HtmlAgilityPack 和 Jumony,感兴趣的可以研究下。当然,火车头采集工具也很方便,不过要付费。下面是整理的代码:

 

   /// <summary>
    /// Html正则处理帮助类
    /// </summary>
    public class HtmlRegex
    {
        /// <summary>
        /// 匹配所有Html标签
        /// </summary>
        const string HTMLALLTAG = @"<[^>]+>|</[^>]+>";

        /// <summary>
        /// 删除所有html标签
        /// </summary>
        /// <param name="content">原HTML代码</param>
        /// <returns></returns>
        public static string RemoveAllHtml(string content)
        {
            return Regex.Replace(content, HTMLALLTAG, "");
        }

        /// <summary>
        /// 根据正则匹配获取指定内容
        /// </summary>
        /// <param name="regStr">正则</param>
        /// <param name="content">原HTML代码</param>
        /// <param name="hashtml">是否包含HTML标签</param>
        /// <returns></returns>
        public static string GetStrByRegex(string regStr, string content, bool hashtml = true)
        {
            string result = string.Empty;
            Regex reg = new Regex(regStr);
            Match mth = reg.Match(content);

            if (mth.Success)
            {
                result = mth.Value;
                if (!hashtml) result = HtmlRegex.RemoveAllHtml(result); //去除html标签

            }
            return result;
        }

        /// <summary>
        /// 获取指定位置的html代码
        /// </summary>
        /// <param name="start">起始字符串</param>
        /// <param name="end">结束字符串</param>
        /// <param name="content">原HTML代码</param>
        /// <param name="hasHtml">是否包含HTML标签</param>
        /// <returns></returns>
        public static string GetStrByRegex(string start, string end, string content, bool hasHtml = true)
        {
            string result = string.Empty;
            string regStr = @"(?is)(" + start + ").*?(" + end + ")";
            Regex reg = new Regex(regStr);
            Match mth = reg.Match(content);
            if (mth.Success)
            {
                result = mth.Value;
                if (!hasHtml) result = HtmlRegex.RemoveAllHtml(result); //去除html标签
            }
            return result;
        }

        /// <summary>
        /// 获取匹配的字符串列表
        /// </summary>
        /// <param name="regStr">正则</param>
        /// <param name="content">原HTML代码</param>
        /// <returns></returns>
        public static List<string> GetStrListByRegex(string regStr, string content)
        {
            List<string> strList = null;
            MatchCollection mc = null;
            try
            {
                Regex reg = new Regex(regStr);
                mc = reg.Matches(content);
                if (mc.Count > 0)
                {
                    strList = new List<string>();
                    for (int i = 0; i < mc.Count; i++)
                    {
                        strList.Add(mc[i].Value);
                    }
                }
            }
            catch
            {
                strList = null;
            }
            return strList;
        }

        /// <summary>
        /// 获取匹配的字符串列表
        /// </summary>
        /// <param name="start">起始字符串</param>
        /// <param name="end">结束字符串</param>
        /// <param name="content">原HTML代码</param>
        /// <returns></returns>
        public static List<string> GetStrListByRegex(string start, string end, string content)
        {
            List<string> strList = null;
            MatchCollection mc = null;
            string regStr = @"(?is)(" + start + ").*?(" + end + ")";
            try
            {
                Regex reg = new Regex(regStr);
                mc = reg.Matches(content);
                if (mc.Count > 0)
                {
                    strList = new List<string>();
                    for (int i = 0; i < mc.Count; i++)
                    {
                        strList.Add(mc[i].Value);
                    }
                }
            }
            catch
            {
                strList = null;
            }
            return strList;
        }

    }

 

posted @ 2019-08-04 21:59  前端小玖  阅读(4629)  评论(0编辑  收藏  举报