我正在使用hpple库在网页上获取某个div的内容。
用法：
NSData* data = [trimmedString dataUsingEncoding:NSUTF8StringEncoding];
TFHpple *xpathParser = [[TFHpple alloc] initWithHTMLData:data];
NSArray *elements = [xpathParser searchWithXPathQuery:@"//div[@id='container']"];
TFHppleElement *element = [elements objectAtIndex:0];
NSString *string = [element content];
NSLog(string);
现在我在想应该用div 容器的内容填充字符串 *字符串？
我收到此错误并崩溃：
*由于未捕获的异常"NSRangeException"而终止应用程序，原因："* -[__NSArrayM对象索引：]：索引 0 超出空数组的边界"
现在我想这是因为它没有用该div 中的任何内容填充数组？一个原因是它没有找到解析我给它的链接，但它没有在 xpathParser 上崩溃，所以我猜它解析得很好？
这告诉我这是我在这一行中的 xpath，这是错误的：
searchWithXPathQuery:@"//div[@id='content']"];
谁能帮我找到文本"我需要下面的所有这些文本："下方div 的 xpath（我已经提供了它上面的所有div。（这是 HTML 页面上的最后一个div）
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<li><a href="/blog/archive/201208">August 2012</a>
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<h2 class="title" id="page-title">How secure are your racks? </h2>
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<div id="node-68" class="node node-article node-promoted clearfix" about="/blog/how-secure-are-your-racks" typeof="sioc:Item foaf:Document">
I need all this text below:
<div class="content">
<div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even" property="content:encoded"><p>Data centre security is a big issue – especially for co-location centres hosting multiple racks for multiple, often competing, clients. Yet whilst security to access the data centre can often be impressive, individual rack level security is often inadequate. Given the number of in-house staff and external engineers, from cablers to storage and server providers, traipsing through a data centre on a near daily basis, poor rack level security is a potential risk.</p>
<p>According to a recent survey conducted by Lieberman Software, 42 percent of IT staff can get unauthorised access to their organisation’s most sensitive information – including the CEO’s private documents. The failing is blamed on management’s naivety when it comes to understanding just how much privileged access their IT departments actually have.</p>
<p>The fact that most racks are secured only with standard handles using a manual key, bears out this survey. Easily broken or bypassed, these locks provide minimal corporate protection; they offer no access control or audit trail of activity. Given the huge ongoing investment in data centres - during 2011-2012, the UK invested an estimated $3.35 billion in data centres; the second highest spending of any country, according to the Datacentre Dynamics Global Industry Census 2011 - extending standard access control techniques to the data centre racks is an important step.</p>
<p>Companies can opt for a rack specific key, combination locks or key cards that are IP enabled to allow an organisation to impose strict control over the time/day an individual is allowed to access the rack. Using standard access control software, all activity is recorded and audited, providing the organisation with a complete list of those who have accessed the racks.</p>
<p>For organisations, this approach adds control and addresses one important aspect of the internal threat. For co-location sites, rack level security removes the need to cage off client specific rack space areas freeing up space that can be used for more racks, delivering a return on investment, as well as improved client security.</p>
</div></div></div> </div>
编辑：基于完整的 HTML，我更改了 XPathQuery
TFHppleElement *element = [xpathParser peekAtSearchWithXPathQuery:@"//div[@id='node-68']"];
// Use peekAtSearchWithXPathQuery as there is only one vdiv with this id so you directly get the element (the function grabs the first element that corresponds to the XPath query)
然后，要获取文本，请遍历其子项
-(NSString*) getStringForTFHppleElement:(TFHppleElement *)element {
NSMutableString *result = [NSMutableString new];
// Iterate recursively through all children
for (TFHppleElement *child in [element children])
[result appendString:[self getStringForTFHppleElement:child]];
// Hpple creates a <text> node when it parses texts
if ([element.tagName isEqualToString:@"text"])
[result appendString:element.content];
return result;
}