iphone - TBXML分析器提供EXC_BAD_ACCESS

我正在使用TBXML分析器来分析一些大的xml文件。 xml文件的结构如下:

<Products>
<Category>
<product></product>
</Category>
</Products>

这是我用来解析xml的代码:

- (void)loadURL {
    // Load and parse an xml string
    Products *product = [[Products alloc] init];
    tbxml = [[TBXML alloc] initWithURL:[NSURL URLWithString:@"SOMELINK"]];

    // If TBXML found a root node, process element and iterate all children

    // Obtain root element
    TBXMLElement * root = tbxml.rootXMLElement;

    // if root element is valid
    if (root) {
        // search for the first category element within the root element's children

        TBXMLElement *Category = [TBXML childElementNamed:@"Category" parentElement:root];

        product.category = [TBXML valueOfAttributeNamed:@"DisplayName" forElement:Category];
        NSLog(@"%@", product.category);
        // if an author element was found

        while ([[TBXML valueOfAttributeNamed:@"DisplayName" forElement:Category] isEqualToString:@"Dames"]) {





            product.category = [TBXML valueOfAttributeNamed:@"DisplayName" forElement:Category];

            TBXMLElement *xmlProduct = [TBXML childElementNamed:@"Product" parentElement:Category];


            while (xmlProduct != nil) {
                Products *product = [[Products alloc] init];

                // extract the title attribute from the book element
                product.productId = [TBXML valueOfAttributeNamed:@"Id" forElement:xmlProduct];

                product.material = [TBXML valueOfAttributeNamed:@"Material" forElement:xmlProduct];

                product.color = [TBXML valueOfAttributeNamed:@"Color" forElement:xmlProduct];

                product.heel = [TBXML valueOfAttributeNamed:@"Heel" forElement:xmlProduct];

                product.lining = [TBXML valueOfAttributeNamed:@"Lining" forElement:xmlProduct];

                product.subcategory = [TBXML valueOfAttributeNamed:@"DisplayName" forElement:xmlProduct];


                NSString * price = [TBXML valueOfAttributeNamed:@"Price" forElement:xmlProduct];



                // if we found a price
                if (price != nil) {
                    // obtain the price from the book element
                    product.price = [NSNumber numberWithFloat:[price floatValue]];
                }



                // add the book object to the dames array and release the resource
                [dames addObject:product];
                [product release];


                // find the next sibling element named "xmlProduct"
                xmlProduct = [TBXML nextSiblingNamed:@"Product" searchFromElement:xmlProduct];
            }




            // find the next sibling element named "Category"
            Category = [TBXML nextSiblingNamed:@"Category" searchFromElement:Category];
        }



        while ([[TBXML valueOfAttributeNamed:@"DisplayName" forElement:Category] isEqualToString:@"Accessoires"]) {





            product.category = [TBXML valueOfAttributeNamed:@"DisplayName" forElement:Category];

            TBXMLElement *xmlProduct = [TBXML childElementNamed:@"Product" parentElement:Category];


            while (xmlProduct != nil) {
                Products *product = [[Products alloc] init];


                product.productId = [TBXML valueOfAttributeNamed:@"Id" forElement:xmlProduct];

                product.material = [TBXML valueOfAttributeNamed:@"Material" forElement:xmlProduct];

                product.color = [TBXML valueOfAttributeNamed:@"Color" forElement:xmlProduct];

                product.subcategory = [TBXML valueOfAttributeNamed:@"DisplayName" forElement:xmlProduct];

                product.heel = [TBXML valueOfAttributeNamed:@"Heel" forElement:xmlProduct];

                product.lining = [TBXML valueOfAttributeNamed:@"Lining" forElement:xmlProduct];


                NSString * price = [TBXML valueOfAttributeNamed:@"Price" forElement:xmlProduct];



                // if we found a price
                if (price != nil) {
                    // obtain the price from the book element
                    product.price = [NSNumber numberWithFloat:[price floatValue]];
                }




                [tassen addObject:product];
                [product release];



                xmlProduct = [TBXML nextSiblingNamed:@"Product" searchFromElement:xmlProduct];
            }



            // find the next sibling element named "Category"
            Category = [TBXML nextSiblingNamed:@"Category" searchFromElement:Category];

        }


        }
    }

总的来说，我有4个类别(由于上面的代码无关，所以将它们的中间2个排除在外)。当我解析前三个类别时，所有功能都可以正常工作，但是当我到达最后一个类别时，就会发生一些奇怪的事情。
Category = [TBXML nextSiblingNamed:@"Category" searchFromElement:Category];行将搜索一个新类别，但是由于没有新类别，它将返回null。我会说解析器是否完成，但是此时解析器崩溃，并在TBXML.M文件(来自tbxml api)中的以下代码中给出EXC_BAD_ACCESS:

TBXMLAttribute * attribute = aXMLElement->firstAttribute;

我不知道为什么，但是也许有人在这里马上看到了。任何帮助将不胜感激!

提前thnx!

最佳答案

问题已经解决了:

此代码提供了错误的访问权限:

 while ([[TBXML valueOfAttributeNamed:@"DisplayName" forElement:Category] isEqualToString:@"Accessoires"])

用while(类别!= nil)解决了它，它起作用了

关于iphone - TBXML分析器提供EXC_BAD_ACCESS，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/6691371/