捕获组无法在NSRegularExpression中工作 [英] Capture groups not working in NSRegularExpression

问题描述

为什么此代码只吐出整个正则表达式匹配而不是捕获组?

Why is this code only spitting out the entire regex match instead of the capture group?

输入

@"A long string containing Name:</td><td>A name here</td> amongst other things"

预期输出

A name here

实际输出

Name:</td><td>A name here</td>

代码

NSString *htmlString = @"A long string containing Name:</td><td>A name here</td> amongst other things";
NSRegularExpression *nameExpression = [NSRegularExpression regularExpressionWithPattern:@"Name:</td>.*\">(.*)</td>" options:NSRegularExpressionSearch error:nil];

NSArray *matches = [nameExpression matchesInString:htmlString
                                  options:0
                                    range:NSMakeRange(0, [htmlString length])];
for (NSTextCheckingResult *match in matches) {
    NSRange matchRange = [match range];
    NSString *matchString = [htmlString substringWithRange:matchRange];
    NSLog(@"%@", matchString);
}

从Apple文档获取的代码. 我知道还有其他库可以执行此操作，但是我想坚持执行此任务的内置功能.<​​/em>

Code taken from Apple docs. I know there are other libraries to do this but i want to stick with what's built in for this task.

推荐答案

您将使用:

for (NSTextCheckingResult *match in matches) {
    //NSRange matchRange = [match range];
    NSRange matchRange = [match rangeAtIndex:1];
    NSString *matchString = [htmlString substringWithRange:matchRange];
    NSLog(@"%@", matchString);
}

这篇关于捕获组无法在NSRegularExpression中工作的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！