XMLParser建议 [英] XMLParser Advice
问题描述
我不确定我做错了什么。我有一个URL，通向一个XML树，如下所示：
I'm not sure what I am doing wrong. I have a URL leading to an XML tree that looks like:
<result>
...
<title>
...
</title>
<body>
...
</body>
...
</result>
我只需要解析文件并获取标题和正文。这是我的object.h：
I just need to parse the file and get the title and body. Here is my object.h:
#import <Foundation/Foundation.h>
@interface Object : NSObject
{
NSString *title;
NSString *description;
}
@property (nonatomic, retain) NSString *title;
@property (nonatomic, retain) NSString *description;
@end
这里是Object.m：
And here is Object.m:
#import "Object.h"
@implementation Object
@synthesize title, description;
-(void) dealloc
{
[title release];
[description release];
[super dealloc];
}
@end
这是我的XMLParser.h ：
Here is my XMLParser.h:
#import <Foundation/Foundation.h>
#import "Object.h"
@interface XMLParser : NSObject <NSXMLParserDelegate>
{
NSMutableString *currentNodeContent;
NSMutableArray *arrayOfObjects;
NSXMLParser *parser;
Object *currentObject;
}
@property (readonly, retain) NSMutableArray *arrayOfObjects;
-(id) loadXMLbyURL:(NSString *)urlString;
@end
最后，XMLParser.m：
And finally, XMLParser.m:
#import "XMLParser.h"
#import "Object.h"
@implementation XMLParser
@synthesize arrayOfObjects;
-(id) loadXMLbyURL:(NSString *)urlString
{
arrayOfObjects = [[NSMutableArray alloc] init];
NSURL *url = [NSURL URLWithString:urlString];
NSData *data = [[[NSData alloc] initWithContentsOfURL:url] autorelease];
parser = [[NSXMLParser alloc] initWithData:data];
parser.delegate = self;
[parser parse];
return self;
}
-(void) dealloc
{
[parser release];
[super dealloc];
}
-(void) parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
if([elementName isEqualToString:@"result"])
{
currentObject = [Object alloc];
}
}
-(void) parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{
if([elementName isEqualToString:@"title"])
{
currentObject.title = currentNodeContent;
}
if([elementName isEqualToString:@"body"])
{
currentObject.description = currentNodeContent;
}
if([elementName isEqualToString:@"result"])
{
[arrayOfObjects addObject:currentObject];
[currentObject release];
currentObject = nil;
[currentNodeContent release];
currentNodeContent = nil;
}
}
-(void) parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
currentNodeContent = (NSMutableString *) [string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
}
@end
在我的主要代码中我制作像这样调用XML解析器：
In my main code I make a call to XML parser like this:
xmlParser = [[XMLParser alloc] loadXMLbyURL:@"www.websiteWithXML.com"];
然而，我的arrayOfObjects中没有任何内容（我知道这是因为当我告诉tableview有as时很多行作为我的数组，没有行）。
However nothing is being placed into my arrayOfObjects (I know this because when I tell a tableview to have as many rows as my array, there are no rows).
请帮忙！提前谢谢！
推荐答案
尝试在每个元素启动时重置currentNodeContent。例如：
Try resetting currentNodeContent inside each of your element starts. For example:
-(void) parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{
if([elementName isEqualToString:@"result"])
{
currentObject = [Object alloc];
}
else if ([elementName isEqualToString:@"title"] || [elementName isEqualToString:@"body"])
{
[currentNodeContent setString:@""];
}
}
然后，当你收到字符时，请追加：
Then, when you receive characters do an append:
-(void) parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
[currentNodeContent appendString:[string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]]];
}
通过执行此操作，您可以处理foundCharacters多次捕获的情况给定元素中的所有字符。
By doing this, you handle the situation where a foundCharacters gets multiple times to capture all of the characters within a given element.
这篇关于XMLParser建议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！
