NSXMLParser strange behavior with \n - ios

Question

I'm developing an iOS 4 application that parses a XML file. A piece of XML is:
<?xml version="1.0" encoding="utf-8" ?>
<cards>
<card id ="0">
<name lang="es">The Mad</name>
<description lang="es">...</description>
</card>
...
</cards>
I use the following method to parse <name lang="es">The Mad</name>.
#pragma mark -
#pragma mark NSXMLParserDelegate methods
- (void)parser:(NSXMLParser *)parser
didStartElement:(NSString *)elementName
namespaceURI:(NSString *)namespaceURI
qualifiedName:(NSString *)qName
attributes:(NSDictionary *)attributeDict
{
NSLog(#"DidStartElement: %#", elementName);
if ([elementName isEqualToString:#"card"])
{
currentCard = [[Card alloc] init];
NSString* arcaneNumber = [attributeDict objectForKey:#"id"];
currentCard.Number = arcaneNumber;
return;
}
if ([elementName isEqualToString:#"name"])
{
if ([[attributeDict objectForKey:#"lang"] isEqualToString:userLanguage])
{
currentProperty = kNameProperty;
return;
}
}
if ([elementName isEqualToString:#"description"])
{
if ([[attributeDict objectForKey:#"lang"] isEqualToString:userLanguage])
{
currentProperty = kDescriptionProperty;
return;
}
}
}
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string
{
if (!currentStringValue)
{
// currentStringValue is an NSMutableString instance variable
currentStringValue = [[NSMutableString alloc] initWithCapacity:50];
}
[currentStringValue appendString:string];
}
- (void) parser:(NSXMLParser *)parser
didEndElement:(NSString *)elementName
namespaceURI:(NSString *)namespaceURI
qualifiedName:(NSString *)qName
{
NSLog(#"DidEndElement: %#", elementName);
if ([elementName isEqualToString:#"card"])
{
[cards setObject:currentCard forKey:currentCard.Number];
[currentCard release];
currentCard = nil;
return;
}
if (currentProperty == kNameProperty)
{
currentProperty = kNoneProperty;
currentCard.Name = [currentStringValue stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
[currentStringValue release];
currentStringValue = nil;
return;
}
if (currentProperty == kDescriptionProperty)
{
currentProperty = kNoneProperty;
currentCard.Description = currentStringValue;
[currentStringValue release];
currentStringValue = nil;
return;
}
}
After, parsing , I get on currentStringValue the following:
\n\nThe Mad
How can avoid these two '\n'? Why am I getting these two '\n'?
This xml file came from a Windows system, and I've used TextWrangler to covert it to Classic Mac format.

Answer 1

The foundCharacters delegate method also gets called for whitespace in between elements. It will get called if there is say a newline between <cards> and <card id=....
I suggest clearing currentStringValue at the top of didStartElement to discard any characters found before the start of the current element and to make sure only the characters inside the current element (not between) are captured by foundCharacters.
At the top of didStartElement, add:
[currentStringValue release];
currentStringValue = nil;
It is possible for an element's value to contain whitespace (so removing them in didEndElement could result in saving values that don't match the xml content).

Answer 2

On your end element method you can try stripping these out yourself from the current text string. Simply try searching for them on the string and replace them with #"". I like replacing these and unwanted blank entries.

Answer 3

Try this it work for me ,
NSString *data= [str stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
Use above line of code in foundCharacters method .
- (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string;
{
NSString *data= [string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
if(dString == nil){
dString = [[NSMutableString alloc] initWithString:data];
}else
{
[dString appendString:data];
}
}
Hope this will help for some one .