//正则表达式
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
//正则表达式需要引用的
using System.Text.RegularExpressions;
namespace Reflection
{
class Program
{
//1.\d表示匹配数字，\D匹配所有的非数字. 表示匹配任意字符，\. 匹配.
//2.[]表示方括号里面的每一个字符或者数字都可以匹配
//3.c{3}表示匹配3个c，c{2,3}表示匹配最少2个c，最多3个c
//4.*表示0个或者多个，+表示一个或者多个，？表示有或者没有
//5.\s表示匹配空格，\S表示匹配非空格,\w匹配所有的字符，\W匹配特殊字符
//6.正则表达式的卡头^，结束为$
//7.（）表示匹配括号里面的字符
//8.\b表示字符的边界
static void Main(string[] args)
{
RegexIsMatch();
RegexMatch();
RegexReplace();
Console.ReadLine();
}
//isMatch用法
private static void RegexIsMatch()
{
string[] values = { "111-22-3333", "111-2-3333" };
string pattern = @"^\d{3}-\d{2}-\d{4}$";
foreach (var value in values)
{
if (Regex.IsMatch(value, pattern))
{
Console.WriteLine("{0} is valid", value);
}
else
{
Console.WriteLine("{0} is not valid", value);
}
}
}
private static void RegexMatch()
{
var input = "This is cdc cdc!";
var pattern = @"\b(\w+)\W(\1)\b";
Match match = Regex.Match(input, pattern);
while (match.Success)
{
Console.WriteLine("Duplication {} found", match.Groups[1].Value);
match = match.NextMatch();
}
}
//正则表达式实现替换
private static void RegexReplace()
{
string patten = @"\b\d+\.\d{2}\b";
//最后一个$&表示匹配上的字符
string replacement = "$$$&";
string input = "total cost:103.64";
Console.WriteLine(Regex.Replace(input, patten, replacement));
}
//正则表达式实现分割
private static void RegexSplit()
{
string input = "1. Egg 2. Bread 3. Mike";
string patten = @"\b\d{1,2}\.\s";
foreach (string item in Regex.Split(input, patten))
{
if (!string.IsNullOrEmpty(item))
{
Console.WriteLine(item);
}
}
}
private static void Matches()
{
MatchCollection matches;
Regex r = new Regex("abc");
matches = r.Matches("123abc4abcd");//获得集合
foreach (Match match in matches)
{
Console.WriteLine("{0} found at position {1}", match.Value, match.Index);
Console.WriteLine("{0}", match.Result("$&, hello,cdc!"));//$&表示匹配的字符
}
}
//mach.Groups的使用
private static void Groups()
{
string input = "Born: July 28, 1989";
string patten = @"\b(\w)\s(\d{1,2}),\s(\d{4})\b";
Match match = Regex.Match(input, patten);
if (match.Success)
{
for (int ctr = 0; ctr < match.Groups.Count; ctr++)
{
Console.WriteLine("Group{0}:{1}", ctr, match.Groups[ctr].Value);
}
}
}
}
}
