版本记录
| 版本号 | 时间 |
|---|---|
| V1.0 | 2018.03.20 |
前言
iOS圈内有几个人大家基本都知道，比如说王巍、唐巧，还有YYKit框架的作者现任职于滴滴的郭曜源 - ibireme等。这里有一篇唐巧对他的专访，还有他的 GitHub - Yaoyuan 和 博客，这里贴出来框架YYKit 框架。接下来几篇我们就一起来看一下这个框架。感兴趣的可以看上面写的几篇。
1. YYKit源码探究（一） —— 基本概览
2. YYKit源码探究（二） —— NSString分类之Hash（一）
3. YYKit源码探究（三） —— NSString分类之Encode and decode（二）
4. YYKit源码探究（四） —— NSString分类之Drawing（三）
回顾
上一篇我们分析了NSString分类NSString+YYAdd的Drawing部分，这一篇我们就看一下Regular Expression部分。
API 接口
/**
Whether it can match the regular expression
@param regex The regular expression
@param options The matching options to report.
@return YES if can match the regex; otherwise, NO.
*/
- (BOOL)matchesRegex:(NSString *)regex options:(NSRegularExpressionOptions)options;
/**
Match the regular expression, and executes a given block using each object in the matches.
@param regex The regular expression
@param options The matching options to report.
@param block The block to apply to elements in the array of matches.
The block takes four arguments:
match: The match substring.
matchRange: The matching options.
stop: A reference to a Boolean value. The block can set the value
to YES to stop further processing of the array. The stop
argument is an out-only argument. You should only ever set
this Boolean to YES within the Block.
*/
- (void)enumerateRegexMatches:(NSString *)regex
options:(NSRegularExpressionOptions)options
usingBlock:(void (^)(NSString *match, NSRange matchRange, BOOL *stop))block;
/**
Returns a new string containing matching regular expressions replaced with the template string.
@param regex The regular expression
@param options The matching options to report.
@param replacement The substitution template used when replacing matching instances.
@return A string with matching regular expressions replaced by the template string.
*/
- (NSString *)stringByReplacingRegex:(NSString *)regex
options:(NSRegularExpressionOptions)options
withString:(NSString *)replacement;
下面我们就详细的看一下这个接口API
1. - (BOOL)matchesRegex:(NSString *)regex options:(NSRegularExpressionOptions)options;
该方法的作用是根据固定的匹配的表达式，判断给定的字符串和调用者是否匹配。
示例调用
下面我们看一下方法的示例调用。
NSString *str = @"A";
BOOL isMatch = [str matchesRegex:@"B" options:NSRegularExpressionCaseInsensitive];
NSLog(@"是否匹配 = %d", isMatch);
看一下输出结果
2018-03-19 10:52:41.174585+0800 JJWebImage[29106:4108904] 是否匹配 = 0
再看另外一个例子
NSString *str = @"A";
BOOL isMatch = [str matchesRegex:@"a" options:NSRegularExpressionCaseInsensitive];
NSLog(@"是否匹配 = %d", isMatch);
下面看输出结果
2018-03-19 11:00:17.839901+0800 JJWebImage[29115:4111852] 是否匹配 = 1
上面这个例子就是NSRegularExpressionCaseInsensitive，也就是不区分大小写的比较。
方法实现
下面我们就看一下方法实现
- (BOOL)matchesRegex:(NSString *)regex options:(NSRegularExpressionOptions)options {
NSRegularExpression *pattern = [NSRegularExpression regularExpressionWithPattern:regex options:options error:NULL];
if (!pattern) return NO;
return ([pattern numberOfMatchesInString:self options:0 range:NSMakeRange(0, self.length)] > 0);
}
2. - (void)enumerateRegexMatches:(NSString *)regex options:(NSRegularExpressionOptions)options usingBlock:(void (^)(NSString *match, NSRange matchRange, BOOL *stop))block;
示例调用
下面我们看一下方法的示例调用。
NSString *str = @"A";
[str enumerateRegexMatches:@"a" options:NSRegularExpressionCaseInsensitive usingBlock:^(NSString * _Nonnull match, NSRange matchRange, BOOL * _Nonnull stop) {
NSLog(@"匹配的字符串 = %@", match);
NSLog(@"匹配的字符串区域 = %ld - %ld", matchRange.location, matchRange.length);
if (matchRange.length > 0) {
*stop = YES;
NSLog(@"匹配的字符串匹配是否停止 = %d", *stop);
}
}];
下面看一下输出结果
2018-03-19 11:20:48.088380+0800 JJWebImage[29143:4119629] 匹配的字符串 = A
2018-03-19 11:20:48.088562+0800 JJWebImage[29143:4119629] 匹配的字符串区域 = 0 - 1
2018-03-19 11:20:48.088602+0800 JJWebImage[29143:4119629] 匹配的字符串匹配是否停止 = 1
方法实现
下面我们就看一下方法实现。
- (void)enumerateRegexMatches:(NSString *)regex
options:(NSRegularExpressionOptions)options
usingBlock:(void (^)(NSString *match, NSRange matchRange, BOOL *stop))block {
if (regex.length == 0 || !block) return;
NSRegularExpression *pattern = [NSRegularExpression regularExpressionWithPattern:regex options:options error:nil];
if (!regex) return;
[pattern enumerateMatchesInString:self options:kNilOptions range:NSMakeRange(0, self.length) usingBlock:^(NSTextCheckingResult *result, NSMatchingFlags flags, BOOL *stop) {
block([self substringWithRange:result.range], result.range, stop);
}];
}
3. - (NSString *)stringByReplacingRegex:(NSString *)regex options:(NSRegularExpressionOptions)options withString:(NSString *)replacement;
返回一个新的字符串，其中包含用模板字符串替换的正则表达式。
示例调用
下面我们看一下方法的示例调用。
NSString *resultStr = [@"Assswsda" stringByReplacingRegex:@"A" options:NSRegularExpressionCaseInsensitive withString:@"h"];
NSLog(@"替换后的字符串 = %@", resultStr);
下面看一下输出结果
2018-03-19 11:47:06.570492+0800 JJWebImage[29153:4126527] 替换后的字符串 = hssswsdh
方法实现
下面我们就看一下方法实现。
- (NSString *)stringByReplacingRegex:(NSString *)regex
options:(NSRegularExpressionOptions)options
withString:(NSString *)replacement; {
NSRegularExpression *pattern = [NSRegularExpression regularExpressionWithPattern:regex options:options error:nil];
if (!pattern) return self;
return [pattern stringByReplacingMatchesInString:self options:0 range:NSMakeRange(0, [self length]) withTemplate:replacement];
}
上面几个方法都有一个枚举值，就是NSRegularExpressionOptions，下面我们就看一下这个枚举值。
typedef NS_OPTIONS(NSUInteger, NSRegularExpressionOptions) {
NSRegularExpressionCaseInsensitive = 1 << 0, /* Match letters in the pattern independent of case. */
NSRegularExpressionAllowCommentsAndWhitespace = 1 << 1, /* Ignore whitespace and #-prefixed comments in the pattern. */
NSRegularExpressionIgnoreMetacharacters = 1 << 2, /* Treat the entire pattern as a literal string. */
NSRegularExpressionDotMatchesLineSeparators = 1 << 3, /* Allow . to match any character, including line separators. */
NSRegularExpressionAnchorsMatchLines = 1 << 4, /* Allow ^ and $ to match the start and end of lines. */
NSRegularExpressionUseUnixLineSeparators = 1 << 5, /* Treat only \n as a line separator (otherwise, all standard line separators are used). */
NSRegularExpressionUseUnicodeWordBoundaries = 1 << 6 /* Use Unicode TR#29 to specify word boundaries (otherwise, traditional regular expression word boundaries are used). */
};
后记
本篇我们分析了Regular Expression部分的功能，主要就是匹配的判断以及文本的替换，喜欢的给个赞~~~
