今天就跟大家聊聊有关C#中怎么利用正则表达式定位字符，可能很多人都不太了解，为了让大家更加了解，小编给大家总结了以下内容，希望大家根据这篇文章可以有所收获。
“定位字符”所代表的是一个虚的字符，它代表一个位置，你也可以直观地认为“定位字符”所代表的是某个字符与字符间的那个微小间隙。
^ 表示其后的字符必须位于字符串的开始处
$ 表示其前面的字符必须位于字符串的结束处
\b 匹配一个单词的边界
\B 匹配一个非单词的边界
另外，还包括：\A 前面的字符必须位于字符处的开始处，\z 前面的字符必须位于字符串的结束处，\Z 前面的字符必须位于字符串的结束处，或者位于换行符前
下面提供一些简单的C#正则表达式之定位字符示例：
string i = "Live for nothing,die for something"; Regex r1 = new Regex("^Live for nothing,die for something$"); //r1.IsMatch(i) true Regex r2 = new Regex("^Live for nothing,die for some$"); //r2.IsMatch(i) false Regex r3 = new Regex("^Live for nothing,die for some"); //r3.IsMatch(i) true string i = @"Live for nothing, die for something";//多行 Regex r1 = new Regex("^Live for nothing,die for something$"); Console.WriteLine("r1 match count:" + r1.Matches(i).Count);//0 Regex r2 = new Regex("^Live for nothing,die for something$", RegexOptions.Multiline); Console.WriteLine("r2 match count:" + r2.Matches(i).Count);//0 Regex r3 = new Regex("^Live for nothing,\r\ndie for something$"); Console.WriteLine("r3 match count:" + r3.Matches(i).Count);//1 Regex r4 = new Regex("^Live for nothing,$"); Console.WriteLine("r4 match count:" + r4.Matches(i).Count);//0 Regex r5 = new Regex("^Live for nothing,$", RegexOptions.Multiline); Console.WriteLine("r5 match count:" + r5.Matches(i).Count);//0 Regex r6 = new Regex("^Live for nothing,\r\n$"); Console.WriteLine("r6 match count:" + r6.Matches(i).Count);//0 Regex r7 = new Regex("^Live for nothing,\r\n$", RegexOptions.Multiline); Console.WriteLine("r7 match count:" + r7.Matches(i).Count);//0 Regex r8 = new Regex("^Live for nothing,\r$"); Console.WriteLine("r8 match count:" + r8.Matches(i).Count);//0 Regex r9 = new Regex("^Live for nothing,\r$", RegexOptions.Multiline); Console.WriteLine("r9 match count:" + r9.Matches(i).Count);//1 Regex r10 = new Regex("^die for something$"); Console.WriteLine("r10 match count:" + r10.Matches(i).Count);//0 Regex r11 = new Regex("^die for something$", RegexOptions.Multiline); Console.WriteLine("r11 match count:" + r11.Matches(i).Count);//1 Regex r12 = new Regex("^"); Console.WriteLine("r12 match count:" + r12.Matches(i).Count);//1 Regex r13 = new Regex("$"); Console.WriteLine("r13 match count:" + r13.Matches(i).Count);//1 Regex r14 = new Regex("^", RegexOptions.Multiline); Console.WriteLine("r14 match count:" + r14.Matches(i).Count);//2 Regex r15 = new Regex("$", RegexOptions.Multiline); Console.WriteLine("r15 match count:" + r15.Matches(i).Count);//2 Regex r16 = new Regex("^Live for nothing,\r$\n^die for something$", RegexOptions.Multiline); Console.WriteLine("r16 match count:" + r16.Matches(i).Count);//1 //对于一个多行字符串，在设置了Multiline选项之后，^和$将出现多次匹配。 string i = "Live for nothing,die for something"; string m = "Live for nothing,die for some thing"; Regex r1 = new Regex(@"\bthing\b"); Console.WriteLine("r1 match count:" + r1.Matches(i).Count);//0 Regex r2 = new Regex(@"thing\b"); Console.WriteLine("r2 match count:" + r2.Matches(i).Count);//2 Regex r3 = new Regex(@"\bthing\b"); Console.WriteLine("r3 match count:" + r3.Matches(m).Count);//1 Regex r4 = new Regex(@"\bfor something\b"); Console.WriteLine("r4 match count:" + r4.Matches(i).Count);//1 //\b通常用于约束一个完整的单词看完上述内容，你们对C#中怎么利用正则表达式定位字符有进一步的了解吗？如果还想了解更多知识或者相关内容，请关注编程网行业资讯频道，感谢大家的支持。
