正则表达式Multiline选项
string i = @"Live for nothing, die for something";//多行 Regex r3 = new Regex("^Live for nothing,\r\ndie for something$"); Console.WriteLine("r3 match count:" + r3.Matches(i).Count);//1 Regex r8 = new Regex("^Live for nothing,\r$"); Console.WriteLine("r8 match count:" + r8.Matches(i).Count);//0 Regex r9 = new Regex("^Live for nothing,\r$", RegexOptions.Multiline); Console.WriteLine("r9 match count:" + r9.Matches(i).Count);//1 //对于一个多行字符串,在设置了Multiline选项之后,^和$将出现多次匹配。