iOS正则匹配

    // 表情的规则
    NSString *emotionPattern = @"\\[[0-9a-zA-Z\\u4e00-\\u9fa5]+\\]";
    
    // @的规则
    NSString *atPattern = @"@[0-9a-zA-Z\\u4e00-\\u9fa5]+";
    
    // #话题#的规则
    NSString *topicPattern = @"#[0-9a-zA-Z\\u4e00-\\u9fa5]+#";
    
    // url链接的规则
    NSString *urlPattern = @"\\b(([\\w-]+://?|www[.])[^\\s()<>]+(?:\\([\\w\\d]+\\)|([^[:punct:]\\s]|/)))";
    
    // | 匹配多个条件,相当于or\或
    NSString *pattern = [NSString stringWithFormat:@"%@|%@|%@|%@", emotionPattern, atPattern, topicPattern, urlPattern];
    
    NSRegularExpression *regex = [[NSRegularExpression alloc] initWithPattern:pattern options:0 error:nil];
    // 2.测试字符串
    NSArray *results = [regex matchesInString:testStr options:0 range:NSMakeRange(0, testStr.length)];
    
    // 3.遍历结果
    for (NSTextCheckingResult *result in results) {
        NSLog(@"%@ %@", NSStringFromRange(result.range), [testStr substringWithRange:result.range]);
    }