iphone : NSXMLParser fails to identify HTML special entity & - iphone

Question

I simply cannot get NSXMLParser to recognize &
here is my XML:
<?xml version="1.1" encoding="UTF-8"?>
<root>
<myURL>http://www.mywebsite.com/info?id=32&page=5</myURL>>
</root>
Here is my parsing code:
-(void)getXml {
NSURL *xmlurl = [[NSURL alloc] initWithString:#"http://www.mywebsite.com/myxml.xml"];
NSXMLParser *xmlParser = [[NSXMLParser alloc] initWithContentsOfURL:xmlurl];
[xmlParser setDelegate:self];
[xmlParser parse];
[xmlParser release];
[dataurl release];
}
- (void)parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError {
NSLog(#"Parser Error: %#", parseError);
}
- (void)parser:(NSXMLParser *)parser validationErrorOccurred:(NSError *)validError {
NSLog(#"Parser validation Error: %#", validError);
}
- (void)parserDidStartDocument:(NSXMLParser *)parser {
NSLog(#"Parser started");
}
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qualifiedName attributes:(NSDictionary *)attributeDict
{
NSLog(#"Found key: %#", elementName);
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string {
NSLog(#"Found Element: %#", string);
}
- (void)parserDidEndDocument:(NSXMLParser *)parser {
NSLog("done"):
}
Here is my output:
Found key: root
Found key: myURL
Found element: http://www.mywebsite.com/info?id=32
Found element: page=5
Found element:
Found key: myURL
The parser is not recognizing the & correctly and is splitting up my url.
I have seen many Stack questions on this issue but none of them have helped and I have read the Apple docs on NSXMLParser as well. Am I missing something here?
I am building with iOS 5.0 to an iPhone 4

Answer 1

Thank you, this is a great insight into the parser process but there were problems using it, maybe due to the features of Xcode 4.5.1
It turned out that assigning a NSString like #"" to a NSMutableString makes it immutable. Instead to set the starting value for the tempString I've had to use
self.tempString = [[NSMutableString alloc] initWithString: #""];
and the parser:foundCharacters method becomes
- (void) parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
[self.tempString appendString:string];
currentNodeContent = (NSMutableString*) [self.tempString stringByTrimmingCharactersInSet: [NSCharacterSet whitespaceAndNewlineCharacterSet]];
}
But that's one problem solved. Thanks.

Answer 2

According to the NSXMLParserDelegate documentation:
The parser object may send the delegate several
parser:foundCharacters: messages to report the characters of an
element. Because string may be only part of the total character
content for the current element, you should append it to the current
accumulation of characters until the element changes.
So the usual pattern of usage is to keep appending to a temporary string until the end of the element is reached:
.h
#property (nonatomic,retain) NSMutableString *tempString;
.m
#synthesize tempString;
- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qualifiedName attributes:(NSDictionary *)attributeDict
{
self.tempString = #"";
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
[self.tempString appendString:string];
}
- (void)parserDidEndDocument:(NSXMLParser *)parser
{
// do something with self.tempString
}