c#使用正则表达式匹配字符串验证URL示例

在System.Text.RegularExpression命名空间里，有正则表达式方法。

using System.Collections.Generic;

using System.Text;
using System.Text.RegularExpressions;

namespace RegexDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            Regex regex = new Regex("China", RegexOptions.IgnoreCase);
            //使用Match方法。
            string source = "China is my mother,My mother is china!";
            Match m = regex.Match(source);
            if (m.Success)
            {
                Console.WriteLine("找到第一个匹配");
            }
            Console.WriteLine(new string('-',9));
            //下面的样例将演示使用Matches方法进行匹配
            MatchCollection matches=regex.Matches(source);
            foreach(Match s in matches)
            {
                if(s.Success)
                    Console.WriteLine("找到了一个匹配");
            }
            Console.ReadLine();
         }
    }
}
[/code]

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

namespace URLRegex
{
    class Program
    {
        static void Main(string[] args)
        {
            string Pattern = @"^(http|https|ftp)\://[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,3}(:[a-zA-Z0-9]*)?/?([a-zA-Z0-9\-\._\?\,\'/\\\+&$％\$#\=~])*$";
            Regex r = new Regex(Pattern);
            string source = "https://www.jb51.net";
            Match m = r.Match(source);
            if (m.Success)
            {
                Console.WriteLine("URL验证成功!");
            }
            else
            {
                Console.WriteLine("URL验证失败!");
            }
            Console.ReadLine();
        }
    }
}