iOS中使用RegexKitLite来试用正则表达式

准备工作，下载RegexKitLite
软件包，解压后有2个文件，需要加载到project中。

然后还要加载framework
libicucore.dylib

，因为RegexKitLite是调用这个里面的API,苹果规定过不能使用私有的api和没有发布的api。实际上RegexKitLite对NSString做了扩展，目前只支持NSString，对我来说也够了...

基本使用的例子（更多信息参看

官方文档
）

1.

[cpp]
view plaincopyprint?

NSString *searchString = @"This is neat.";

NSString *regexString = @"(//w+)//s+(//w+)//s+(//w+)";

NSRange matchedRange = NSMakeRange(NSNotFound, 0UL);

NSError *error = NULL;
matchedRange = [searchString rangeOfRegex:regexString options:RKLNoOptions inRange:searchRange capture:2L error:&error];

NSLog(@"matchedRange: %@", NSStringFromRange(matchedRange));

// 2008-03-18 03:51:16.530 test[51583:813] matchedRange: {5, 2}，//匹配到‘is‘

NSString *matchedString = [searchString substringWithRange:matchedRange];

NSLog(@"matchedString: '%@'", matchedString);

// 2008-03-18 03:51:16.532 test[51583:813] matchedString: 'is' //生成子字符串

[cpp]
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NSString *searchString = @"This is neat.";

NSString *regexString = @"(//w+)//s+(//w+)//s+(//w+)";

NSString *matchedString = [searchString stringByMatching:regexString capture:2L];

NSLog(@"matchedString: '%@'", matchedString);

// 2008-03-18 03:53:42.949 test[51583:813] matchedString: 'is'

NSString *searchString  = @"This is neat.";
NSString *regexString   = @"(//w+)//s+(//w+)//s+(//w+)";
NSString *matchedString = [searchString stringByMatching:regexString capture:2L];
NSLog(@"matchedString: '%@'", matchedString);
// 2008-03-18 03:53:42.949 test[51583:813] matchedString: 'is'

3.查找和替换，加括号和概念和Python中的一样，$1指代第一个括号中的内容

[cpp]
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NSString *searchString = @"This is neat.";

NSString *regexString = @"//b(//w+)//b";

NSString *replaceWithString = @"{$1}";

NSString *replacedString = NULL;
replacedString = [searchString stringByReplacingOccurrencesOfRegex:regexString withString:replaceWithString];

//NSMutableString可以直接替换，并返回替换的次数
NSLog(@"replaced string: '%@'", replacedString);

// 2008-07-01 19:03:03.195 test[68775:813] replaced string: '{This} {is} {neat}.'

NSMutableString *mutableString = [NSMutableString stringWithString:@"This is neat."];

NSString *regexString = @"//b(//w+)//b";

NSString *replaceWithString = @"{$1}";

NSUInteger replacedCount = 0UL;
replacedCount = [mutableString replaceOccurrencesOfRegex:regexString withString:replaceWithString];

NSLog(@"count: %lu string: '%@'", (u_long)replacedCount, mutableString);

// 2008-07-01 21:25:43.433 test[69689:813] count: 3 string: '{This} {is} {neat}.'

[cpp]
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NSString *searchString = @"This is neat.";

NSString *regexString = @"//s+";

NSArray *splitArray = NULL;
splitArray = [searchString componentsSeparatedByRegex:regexString];

// splitArray == { @"This", @"is", @"neat." }

NSLog(@"splitArray: %@", splitArray);

NSString *searchString = @"This is neat.";
NSString *regexString  = @"//s+";
NSArray  *splitArray   = NULL;
splitArray = [searchString componentsSeparatedByRegex:regexString];
// splitArray == { @"This", @"is", @"neat." }
NSLog(@"splitArray: %@", splitArray);

5.返回所有匹配的字符串数组，这个例子中虽然有多个括号，但是

componentsMatchedByRegex不管

[cpp]
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NSString *searchString = @"$10.23, $1024.42, $3099";

NSString *regexString = @"//$((//d+)(?://.(//d+)|//.?))";

NSArray *matchArray = NULL;
matchArray = [searchString componentsMatchedByRegex:regexString];

// matchArray == { @"$10.23", @"$1024.42", @"$3099" };

NSLog(@"matchArray: %@", matchArray);

6.返回所有匹配的字符串数组处理所有的括号
NSString *searchString = @"$10.23, $1024.42, $3099";

NSString *regexString = @"//$((//d+)(?://.(//d+)|//.?))";

NSArray *capturesArray = NULL;
capturesArray = [searchString arrayOfCaptureComponentsMatchedByRegex:regexString];

/* capturesArray ==
[NSArray arrayWithObjects:

[NSArray arrayWithObjects: @"$10.23", @"10.23", @"10", @"23", NULL],

[NSArray arrayWithObjects:@"$1024.42", @"1024.42", @"1024", @"42", NULL],

[NSArray arrayWithObjects: @"$3099", @"3099", @"3099", @"", NULL],

NULL];
*/
NSLog(@"capturesArray: %@", capturesArray);

输出结果：
shell% ./capturesArray↵
2009-05-06 03:25:46.852 capturesArray[69981:10b] capturesArray: (

(
"$10.23",
"10.23",
10,
23
),
(
"$1024.42",
"1024.42",

1024,
42
),
(
"$3099",
3099,
3099,
""
)
)

NSString *searchString = @"$10.23, $1024.42, $3099";
NSString *regexString = @"//$((//d+)(?://.(//d+)|//.?))";
NSArray *matchArray = NULL;
matchArray = [searchString componentsMatchedByRegex:regexString];
// matchArray == { @"$10.23", @"$1024.42", @"$3099" };
NSLog(@"matchArray: %@", matchArray);
6.返回所有匹配的字符串数组处理所有的括号
NSString *searchString = @"$10.23, $1024.42, $3099";
NSString *regexString = @"//$((//d+)(?://.(//d+)|//.?))";
NSArray *capturesArray = NULL;
capturesArray = [searchString arrayOfCaptureComponentsMatchedByRegex:regexString];
/* capturesArray ==
[NSArray arrayWithObjects:
[NSArray arrayWithObjects: @"$10.23", @"10.23", @"10", @"23", NULL],
[NSArray arrayWithObjects:@"$1024.42", @"1024.42", @"1024", @"42", NULL],
[NSArray arrayWithObjects: @"$3099", @"3099", @"3099", @"", NULL],
NULL];
*/
NSLog(@"capturesArray: %@", capturesArray);
输出结果：
shell% ./capturesArray↵
2009-05-06 03:25:46.852 capturesArray[69981:10b] capturesArray: (
(
"$10.23",
"10.23",
10,
23
),
(
"$1024.42",
"1024.42",
1024,
42
),
(
"$3099",
3099,
3099,
""
)
)