时间:2020-10-28 21:52:27 | 栏目:.NET代码 | 点击:次
使用Regex类需要引用命名空间:using System.Text.RegularExpressions;
利用Regex类实现验证
示例1:注释的代码所起的作用是相同的,不过一个是静态方法,一个是实例方法
var source = "刘备关羽张飞孙权何问起"; //Regex regex = new Regex("孙权"); //if (regex.IsMatch(source)) //{ // Console.WriteLine("字符串中包含有敏感词:孙权!"); //} if (Regex.IsMatch(source, "孙权")) { Console.WriteLine("字符串中包含有敏感词:孙权!"); } Console.ReadLine();
示例2:使用带两个参数的构造函数,第二个参数指示忽略大小写,很常用
var source = "123abc345DEf"; Regex regex = new Regex("def",RegexOptions.IgnoreCase); if (regex.IsMatch(source)) { Console.WriteLine("字符串中包含有敏感词:def!"); } Console.ReadLine();
使用Regex类进行替换
示例1:简单情况
var source = "123abc456ABC789"; // 静态方法 //var newSource=Regex.Replace(source,"abc","|",RegexOptions.IgnoreCase); // 实例方法 Regex regex = new Regex("abc", RegexOptions.IgnoreCase); var newSource = regex.Replace(source, "|"); Console.WriteLine("原字符串:"+source); Console.WriteLine("替换后的字符串:" + newSource); Console.ReadLine();
结果:
原字符串:123abc456ABC789
替换后的字符串:123|456|789
示例2:将匹配到的选项替换为html代码,我们使用了MatchEvaluator委托
var source = "123abc456ABCD789"; Regex regex = new Regex("[A-Z]{3}", RegexOptions.IgnoreCase); var newSource = regex.Replace(source,new MatchEvaluator(OutPutMatch)); Console.WriteLine("原字符串:"+source); Console.WriteLine("替换后的字符串:" + newSource); Console.ReadLine(); //柔城 private static string OutPutMatch(Match match) { return "<b>" +match.Value+ "</b>"; }
输出:
原字符串:123abc456ABCD789
替换后的字符串:123<b>abc</b>456<b>ABC</b>D789
C#正则表达式Regex常用匹配
在线测试:http://tool.hovertree.com/a/zz/
#region 身份证号码正则表达式 //何问起 Console.WriteLine("请输入一个身份证号码"); string id = Console.ReadLine(); bool b4 = Regex.IsMatch(id, @"^\d{15}|\d{18}$"); bool b5 = Regex.IsMatch(id, @"^(\d{15}|\d{18})$"); Console.WriteLine(b4); Console.WriteLine(b5); #endregion #region 匹配电话号码 //hovertree Console.WriteLine("请输入电话号码"); string phone = Console.ReadLine(); bool b = Regex.IsMatch(phone, @"^((\d{3,4}\-\d?{7,8})|(\d{5}))$"); Console.WriteLine(b); #endregion #region 匹配email的regex //hovertree Console.WriteLine("请输入Email地址"); string email = Console.ReadLine(); bool bhvt = Regex.IsMatch(email, @"^\w+@\w+\.\w+$"); Console.WriteLine(bhvt); #endregion #region 匹配ip地址的regex //hovertree Console.WriteLine("请输入一个IP地址"); string ip = Console.ReadLine(); bool bkly = Regex.IsMatch(ip, @"^\d{1,3}(\.\d{1,3}){3}$"); Console.WriteLine(bkly); #endregion #region 匹配日期合法regex //何问起 Console.WriteLine("请输入一个日期"); string date = Console.ReadLine(); bool bhovertree = Regex.IsMatch(date, @"^\d{4}\-\d{1,2}\-\d{1,2}$"); Console.WriteLine(bhovertree); #endregion #region 匹配url地址的regex //"http://hovertree.com" //"http://keleyi.com/a/bjae/h1o76nuh.htm?id=3&name=aaa" //"https://s.taobao.com/search?q=hover+tree&js=1&stats_click=search_radio_all%3A1&initiative_id=staobaoz_20151204&ie=utf8" //"ftp://127.0.0.1/myslider.txt" Console.WriteLine("请输入url地址"); string url = Console.ReadLine(); bool bkeleyi = Regex.IsMatch(url, @"^[a-zA-Z]+://.+$"); Console.WriteLine(bkeleyi); #endregion