//实例1 string msg = "你aaa好aa啊!a哈哈"; msg = Regex.Replace(msg, "a+", "A"); //输出结果 你A好A啊!A哈哈 把多个相同的字符替换成一个 //实例2 string msg2 = "wer 'adsf' adf 'asfdasdf' adsf 'ss 'asdff"; msg2 = Regex.Replace(msg2, "'(.+?)'", "【$1】"); //输出结果 wer 【adsf】 adf 【asfdasdf】 adsf 【ss 】asdf //实例3 string msg3 = "罗分明18312345678lqwvje15288888888"; msg3 = Regex.Replace(msg3, "([0-9]{3})[0-9]{4}([0-9]{4})", "$1****$2"); //输出结果罗分明183****5678lqwvje152****8888 //实例4 string msg4 = "tomorrow row";//把row改为line tomorrow中的row不能更换 msg4 = Regex.Replace(msg4, @"\brow\b", "line"); //实例5 string msg5 = "hao are you,welcome to you";//找出句子中三个字母的单词 MatchCollection mc = Regex.Matches(msg5, @"\b[a-z]{3}\b", RegexOptions.IgnoreCase);//RegexOptions.IgnoreCase不区分大小写 StringBuilder sb = new StringBuilder(); foreach(Match m in mc) { sb.AppendLine(m.Value); } //实例6 string msg6 = "# ### #### ### ## # ###"; MatchCollection mc2 = Regex.Matches(msg6, @"\b###\b");//输出的是0个,因为\b是单词标识 StringBuilder sb2 = new StringBuilder(); foreach (Match m in mc2) { sb2.AppendLine(m.Value); } //实例7 string msg7 = "我是罗罗罗分分明明明明明"; msg7= Regex.Replace(msg7, @"(.)\1+","$1"); //实例8 string msg8 = "提取年月日07/09/2017提取年月日07/09/2017";//提取之后格式变为 msg8 = Regex.Replace(msg8, @"(\d{2})/(\d{2})/(\d{4})", "$3-$1-$2");