C#中使用正则表达式匹配字符串的方法如下：
1.使用System.Text.RegularExpressions命名空间；
2.使用Matches()方法匹配字符串，格式如下：
MatchCollection Matches = Regex.Matches(Str, Pattern, RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture);
其中Str表示输入字符串，Pattern表示匹配模式，RegexOptions.IgnoreCase表示忽略大小写，RegexOptions.ExplicitCapture表示改变收集匹配方式。
3.匹配结果保存在MatchCollection集合中，可以通过循环遍历结果集取出Match对象的结果。
TestRagular.cs:
01.using System;
02.using System.Text.RegularExpressions;
03.
04.namespace Magci.Test.Strings
05.{
06. public class TestRegular
07. {
08. public static void WriteMatches(string str, MatchCollection matches)
09. {
10. Console.WriteLine("\nString is : " + str);
11. Console.WriteLine("No. of matches : " + matches.Count);
12. foreach (Match nextMatch in matches)
13. {
14. //取出匹配字符串和最多10个外围字符
15. int Index = nextMatch.Index;
16. string result = nextMatch.ToString();
17. int charsBefore = (Index < 5) ? Index : 5;
18. int fromEnd = str.Length - Index - result.Length;
19. int charsAfter = (fromEnd < 5) ? fromEnd : 5;
20. int charsToDisplay = charsBefore + result.Length + charsAfter;
21.
22. Console.WriteLine("Index: {0},\tString: {1},\t{2}", Index, result, str.Substring(Index - charsBefore, charsToDisplay));
23. }
24. }
25.
26. public static void Main()
27. {
28. string Str = @"My name is Magci, for short mgc. I like c sharp!";
29.
30. //查找“gc”
31. string Pattern = "gc";
32. MatchCollection Matches = Regex.Matches(Str, Pattern, RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture);
33.
34. WriteMatches(Str, Matches);
35.
36. //查找以“m”开头，“c”结尾的单词
37. Pattern = @"\bm\S*c\b";
38. Matches = Regex.Matches(Str, Pattern, RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture);
39.
40. WriteMatches(Str, Matches);
41. }
42. }
1.使用System.Text.RegularExpressions命名空间；
2.使用Matches()方法匹配字符串，格式如下：
MatchCollection Matches = Regex.Matches(Str, Pattern, RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture);
其中Str表示输入字符串，Pattern表示匹配模式，RegexOptions.IgnoreCase表示忽略大小写，RegexOptions.ExplicitCapture表示改变收集匹配方式。
3.匹配结果保存在MatchCollection集合中，可以通过循环遍历结果集取出Match对象的结果。
TestRagular.cs:
01.using System;
02.using System.Text.RegularExpressions;
03.
04.namespace Magci.Test.Strings
05.{
06. public class TestRegular
07. {
08. public static void WriteMatches(string str, MatchCollection matches)
09. {
10. Console.WriteLine("\nString is : " + str);
11. Console.WriteLine("No. of matches : " + matches.Count);
12. foreach (Match nextMatch in matches)
13. {
14. //取出匹配字符串和最多10个外围字符
15. int Index = nextMatch.Index;
16. string result = nextMatch.ToString();
17. int charsBefore = (Index < 5) ? Index : 5;
18. int fromEnd = str.Length - Index - result.Length;
19. int charsAfter = (fromEnd < 5) ? fromEnd : 5;
20. int charsToDisplay = charsBefore + result.Length + charsAfter;
21.
22. Console.WriteLine("Index: {0},\tString: {1},\t{2}", Index, result, str.Substring(Index - charsBefore, charsToDisplay));
23. }
24. }
25.
26. public static void Main()
27. {
28. string Str = @"My name is Magci, for short mgc. I like c sharp!";
29.
30. //查找“gc”
31. string Pattern = "gc";
32. MatchCollection Matches = Regex.Matches(Str, Pattern, RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture);
33.
34. WriteMatches(Str, Matches);
35.
36. //查找以“m”开头，“c”结尾的单词
37. Pattern = @"\bm\S*c\b";
38. Matches = Regex.Matches(Str, Pattern, RegexOptions.IgnoreCase | RegexOptions.ExplicitCapture);
39.
40. WriteMatches(Str, Matches);
41. }
42. }
43.}
本文转自My_King1 51CTO博客，原文链接：http://blog.51cto.com/apprentice/1360721，如需转载请自行联系原作者
