XMLParser nach der Analyse gibt NULL-Werte im Wörterbuch

Question

Ich versuche, die XML zu JSON-Format zu analysieren. Ich benutze die externe Bibliothek von XMLReader (die von Github heruntergeladen wurde). Nach dem Parsen des XML bekomme ich die NULL Ergebnisse. Ich habe versucht, die NSError-Werte zu drucken, die den Fehler gibt "NSErrorDomain-Code = 4 und Dokument ist leer". Was kann ich tun? Kann jemand dazu beitragen?

• Hier ist mein ViewDidLoad() Code:

  NSDictionary *xmlDict = [[NSDictionary alloc]init]; 
  
      NSError *parseError = nil; 
  
      xmlDict = [XMLReader dictionaryForXMLString:@"abc.xml"]; // which call's the XMLReader Class Method 
  
      NSLog(@"MAIN CLASS OF Dictionary: %@",xmlDict); // Gives the NULL Results. 
  

• Hier ist mein XMLReader.h-Code

  #import <Foundation/Foundation.h> 
  
      @interface XMLReader : NSObject <NSXMLParserDelegate> 
       { 
       NSMutableArray *dictionaryStack; 
       NSMutableString *textInProgress; 
       NSError *errorPointer; 
       } 
  
       + (NSDictionary *)dictionaryForXMLData:(NSData *)data error:(NSError **)errorPointer; 
       + (NSDictionary *)dictionaryForXMLString:(NSString *)string error:(NSError **)errorPointer; 
  
        @end 
  

  • Hier mein XMLReader ist. m Code

     #import "XMLReader.h" 
    
         NSString *const kXMLReaderTextNodeKey = @"text"; 
    
          @interface XMLReader (Internal) 
    
         - (id)initWithError:(NSError **)error; 
          - (NSDictionary *)objectWithData:(NSData *)data; 
    
          @end 
    
          @implementation XMLReader 
    
          #pragma mark - 
          #pragma mark Public methods 
    
          + (NSDictionary *)dictionaryForXMLData:(NSData *)data error:(NSError **)error 
           { 
           XMLReader *reader = [[XMLReader alloc] initWithError:error]; 
           NSDictionary *rootDictionary = [reader objectWithData:data]; 
    
          return rootDictionary; 
           } 
    
          + (NSDictionary *)dictionaryForXMLString:(NSString *)string error:(NSError **)error 
           { 
           NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding]; 
           return [XMLReader dictionaryForXMLData:data error:error]; 
            } 
    
          #pragma mark Parsing 
    
           - (NSDictionary *)objectWithData:(NSData *)data 
            { 
            // Clear out any old data 
    
             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 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 = [[NSMutableString alloc] init]; 
          } 
    
           // Pop the current dict 
            [dictionaryStack removeLastObject]; 
          } 
    
          - (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string 
          { 
           // Build the text value 
            [textInProgress appendString:string]; 
           } 
    
             - (void)parser:(NSXMLParser *)parser parseErrorOccurred:(NSError *)parseError 
           { 
             // Set the error pointer to the parser's error object 
            errorPointer = parseError; 
             NSLog(@"ERROR PONIT IS: %@",errorPointer); 
            } 
    
          @end 
    

Also, in diesem Code i für das Parsen von XML-Daten zu Wörterbuch-Format verwenden. Kann mir jemand zu diesem Thema helfen?

Answer 1

Versuchen Sie etwas wie das. Decalre unten Methode in AppDelegate.h Datei

+(void)downloadDataFromURL:(NSURL *)url withCompletionHandler:(void(^)(NSData *data))completionHandler; 

die Methodendefinition in AppDelegate.m

+(void)downloadDataFromURL:(NSURL *)url withCompletionHandler:(void (^)(NSData *))completionHandler{ 
// Instantiate a session configuration object. 
     NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration]; 

// Instantiate a session object. 
     NSURLSession *session = [NSURLSession sessionWithConfiguration:configuration]; 

// Create a data task object to perform the data downloading. 
     NSURLSessionDataTask *task = [session dataTaskWithURL:url completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) { 

    if (error != nil) { 
     // If any error occurs then just display its description on the console. 
     NSLog(@"%@", [error localizedDescription]); 
    } 
    else{ 
     // If no error occurs, check the HTTP status code. 
     NSInteger HTTPStatusCode = [(NSHTTPURLResponse *)response statusCode]; 

     // If it's other than 200, then show it on the console. 
     if (HTTPStatusCode != 200) { 
      NSLog(@"HTTP status code = %d", HTTPStatusCode); 
     } 

     // Call the completion handler with the returned data on the main thread. 
     [[NSOperationQueue mainQueue] addOperationWithBlock:^{ 
      completionHandler(data); 
     }]; 
    } 
}]; 
} 

Jetzt Rufen Sie diese Methode von Ihrem Viewcontroller wie dies in viewDidLoad Datei hinzufügen

[AppDelegate downloadDataFromURL:url withCompletionHandler:^(NSData *data) { 
    // Make sure that there is data. 
    if (data != nil) { 
     xmlDict = [XMLReader dictionaryForXMLData:data error:&parseError]; 
    } 
}]; 

Hoffnung Dies wird Ihnen helfen