ios - HTML表格解析xcode

Question

我正在尝试解析:[www.neiu.edu/~neiutemp/PhoneBook/alpha.htm] 使用 TFHPPLE 解析器，我正在寻找表中每个 TR(行)的第一个 TD(第一列) .这里 TD 的所有属性都是相同的。我无法区分 TD。
我能够获取所有 HTML 代码，但无法从每个 TR 获取第一个 TD。在 //3(在代码中)tutorialsNodes 之后为空。的输出

NSLog(@"Nodes are : %@",[tutorialsNodes description]);

是

Practice1[62351:c07] Nodes are : ().

I can't see what's wrong. Any help would be appreciated.My code to parse this URL:

NSURL *tutorialsUrl = [NSURL URLWithString:@"http://www.neiu.edu/~neiutemp/PhoneBook/alpha.htm"];
NSData *tutorialsHtmlData = [NSData dataWithContentsOfURL:tutorialsUrl];

// 2
TFHpple *tutorialsParser = [TFHpple hppleWithHTMLData:tutorialsHtmlData];

// 3
NSString *tutorialsXpathQueryString = @"//TR/TD";
NSArray *tutorialsNodes = [tutorialsParser searchWithXPathQuery:tutorialsXpathQueryString];
NSLog(@"Nodes are : %@",[tutorialsNodes description]);
// 4
NSMutableArray *newTutorials = [[NSMutableArray alloc] initWithCapacity:0];
for (TFHppleElement *element in tutorialsNodes) {
    // 5
    Tutorial *tutorial = [[Tutorial alloc] init];
    [newTutorials addObject:tutorial];

    // 6
    tutorial.title = [[element firstChild] content];

    // 7
    tutorial.url = [element objectForKey:@"href"];

    NSLog(@"title is: %@",[tutorial.title description]);
}

// 8
_objects = newTutorials;
[self.tableView reloadData];

Answer 1

如果您使用 @"//tr/td" 而不是 @"//TR/TD"，这应该可以工作。

不过，看看您的 HTML，因为它的作者显然不知道如何拼写 CSS，所以您在整个源代码中都隐藏了字体标签。因此，您的下一行代码显然取自优秀的 Hpple tutorial by Matt Galloway on Ray Wenderlich's site , 说:

tutorial.title = [[element firstChild] content];

但这在这里行不通，因为对于您的大部分条目，firstChild 不是文本，而是一种字体 标签。所以你可以检查它是否是这样的字体标签:

TFHppleElement *subelement = [element firstChild];
if ([[subelement tagName] isEqualToString:@"font"])
    subelement = [subelement firstChild];
tutorial.title = [subelement content];

或者，您可以只搜索 @"//tr/td/font" 而不是 @"//tr/td"。这里有很多方法。诀窍(就像所有 HTML 解析一样)是使其相当健壮，这样您就不会对页面进行微小的外观调整。

显然，您的 HTML 中没有 URL，因此该代码不适用于此处。

无论如何，我希望这足以让您继续前进。

---

您报告有问题，所以我想我应该提供更完整的代码示例:

NSURL *tutorialsUrl = [NSURL URLWithString:@"http://www.neiu.edu/~neiutemp/PhoneBook/alpha.htm"];
NSData *tutorialsHtmlData = [NSData dataWithContentsOfURL:tutorialsUrl];

TFHpple *tutorialsParser = [TFHpple hppleWithHTMLData:tutorialsHtmlData];

NSString *tutorialsXpathQueryString = @"//tr/td";
NSArray *tutorialsNodes = [tutorialsParser searchWithXPathQuery:tutorialsXpathQueryString];

if ([tutorialsNodes count] == 0)
    NSLog(@"nothing there");
else
    NSLog(@"There are %d nodes", [tutorialsNodes count]);

NSMutableArray *newTutorials = [[NSMutableArray alloc] initWithCapacity:0];
for (TFHppleElement *element in tutorialsNodes) {

    Tutorial *tutorial = [[Tutorial alloc] init];
    [newTutorials addObject:tutorial];

    TFHppleElement *subelement = [element firstChild];
    if ([[subelement tagName] isEqualToString:@"font"])
        subelement = [subelement firstChild];
    tutorial.title = [subelement content];

    NSLog(@"title is: %@", [tutorial.title description]);
}

这会产生以下输出:

2013-05-10 19:39:42.027 hpple-test[33881:c07] There are 10773 nodes2013-05-10 19:39:42.028 hpple-test[33881:c07] title is: A2013-05-10 19:39:46.027 hpple-test[33881:c07] title is: (null)2013-05-10 19:39:46.698 hpple-test[33881:c07] title is: (null)2013-05-10 19:39:47.333 hpple-test[33881:c07] title is: (null)2013-05-10 19:39:47.827 hpple-test[33881:c07] title is: (null)2013-05-10 19:39:48.358 hpple-test[33881:c07] title is: (null)2013-05-10 19:39:49.133 hpple-test[33881:c07] title is: (null)2013-05-10 19:39:49.775 hpple-test[33881:c07] title is: Abay, Hiwet B2013-05-10 19:39:50.326 hpple-test[33881:c07] title is: H-Abay2013-05-10 19:39:50.992 hpple-test[33881:c07] title is: 773-442-51402013-05-10 19:39:51.597 hpple-test[33881:c07] title is: (null)2013-05-10 19:39:52.092 hpple-test[33881:c07] title is: Controller2013-05-10 19:39:52.598 hpple-test[33881:c07] title is: E2013-05-10 19:39:53.149 hpple-test[33881:c07] title is: 2232013-05-10 19:39:55.040 hpple-test[33881:c07] title is: Abbruscato, Terence 2013-05-10 19:39:55.806 hpple-test[33881:c07] title is: T-Abbruscato2013-05-10 19:39:56.525 hpple-test[33881:c07] title is: 773-442-5339...