iphone - nsxml 解析器问题

Question

我对 iPhone 很满意，以前也这样做过，但现在不明白。我正在使用 XMLParser 并得到如下所示的响应:

username =         {
        text = akhildas;
        type = string;
    };

相反，我期望的是

username = akhildas

我已经做的是:

- (NSDictionary *)objectWithData:(NSData *)data
{
// Clear out any old data
[dictionaryStack release];
[textInProgress release];

dictionaryStack = [[NSMutableArray alloc] init];
textInProgress = [[NSMutableString alloc] init];

// Initialize the stack with a fresh dictionary
[dictionaryStack addObject:[NSMutableDictionary dictionary]];

// Parse the XML
NSXMLParser *parser = [[NSXMLParser alloc] initWithData:data];
parser.delegate = self;
BOOL success = [parser parse];

// Return the stack's root dictionary on success
if (success)
{
    NSDictionary *resultDict = [dictionaryStack objectAtIndex:0];
    return resultDict;
}

return nil;
}

#pragma mark -
#pragma mark NSXMLParserDelegate methods

- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict
{


// Get the dictionary for the current level in the stack
NSMutableDictionary *parentDict = [dictionaryStack lastObject];

// Create the child dictionary for the new element, and initilaize it with the attributes
NSMutableDictionary *childDict = [NSMutableDictionary dictionary];
[childDict addEntriesFromDictionary:attributeDict];

// If there's already an item for this key, it means we need to create an array
id existingValue = [parentDict objectForKey:elementName];
if (existingValue)
{
    NSMutableArray *array = nil;
    if ([existingValue isKindOfClass:[NSMutableArray class]])
    {
        // The array exists, so use it
        array = (NSMutableArray *) existingValue;
    }
    else
    {
        // Create an array if it doesn't exist
        array = [NSMutableArray array];
        [array addObject:existingValue];

        // Replace the child dictionary with an array of children dictionaries
        [parentDict setObject:array forKey:elementName];
    }

    // Add the new child dictionary to the array
    [array addObject:childDict];

}
else
{
    // No existing value, so update the dictionary
    [parentDict setObject:childDict forKey:elementName];
}

// Update the stack
[dictionaryStack addObject:childDict];
}

- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName
{


// Update the parent dict with text info
NSMutableDictionary *dictInProgress = [dictionaryStack lastObject];

// Set the text property
if ([textInProgress length] > 0)
{
    [dictInProgress setObject:textInProgress forKey:kXMLReaderTextNodeKey];

    // Reset the text
    [textInProgress release];
    textInProgress = [[NSMutableString alloc] init];
}

// Pop the current dict
[dictionaryStack removeLastObject];
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
// Build the text value
[textInProgress appendString:string];
}

有人遇到同样的问题并且解决得很好吗？

Answer 1

我总是尝试避免基于回调(SAX)的 NSXMLParser，转而使用 DOM 解析器来为您创建 DOM 树模型。我发现 DOM 解析器更容易处理。

我最喜欢的是 GDataXML 解析器(由 Google 开发)。它非常可靠且易于使用。它仅由 2 个文件(和 libxml2 库)组成，但功能非常强大。它使您不必查找委托(delegate)方法，也不必怀疑是否正确遵循 XML 结构并以正确的方式提取对象。

将 XML 文档映射到 Objective-C 对象树可以像下面这样简短地完成:

NSData  *xmlData = [[NSMutableData  alloc] initWithContentsOfFile:filePath];
 NSError  *error;
 GDataXMLDocument *doc = [[GDataXMLDocument alloc] initWithData:xmlData 
        options:0 error:&error];
 if (doc != nil)NSLog(@"%@", doc.rootElement);

请参阅这个非常流行的 iPhone XML 解析教程，其中解释了 GDataXML:

http://www.raywenderlich.com/725/how-to-read-and-write-xml-documents-with-gdataxml

希望它能让您通过跟踪和解析 XML 数据变得更轻松。