示例：查找出字符串中包含的url
string text = "FirstUrl: ,SecondUrl: ";
string pattern = @"\b(\S+)://(\S+)\b"; //匹配URL的模式
MatchCollection mc = Regex.Matches(text, pattern); //满足pattern的匹配集合
Console.WriteLine("文本中包含的URL地址有：");
foreach (Match match in mc)
{
Console.WriteLine(match.Value);
}
Console.ReadLine();
结果：
Group类
示例：找到字符串中包含的url，并找出每个url的协议和域名地址
string text = "FirstUrl: ,SecondUrl: ";
string pattern = @"\b(?<protocol>\S+)://(?<address>\S+)\b"; //匹配URL的模式,并分组
MatchCollection mc = Regex.Matches(text, pattern); //满足pattern的匹配集合
Console.WriteLine("文本中包含的URL地址有：");
foreach (Match match in mc)
{
GroupCollection gc = match.Groups;
string outputText = "URL:" + match.Value + "；Protocol:" + gc["protocol"].Value + "；Address:" + gc["address"].Value;
Console.WriteLine(outputText);
}
Console.Read();
说明："?<protocol>"和"?<address>"定义了每个组的别名protocol和address
，