以下代碼泄漏了一些東西

Question

我的應用似乎在某些行崩潰了（控制台沒有給出確切的主意）。 我剛收到程序收到的ERROR信號。 您能否讓我知道以下代碼中是否存在泄漏或其他問題...我正在釋放dealloc方法中的屬性；

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
    self.curr_rep_date = [[NSMutableString alloc] init];
    retrievedArray = [[Shared sharedManager] books];

    NSString *urlstr_replist_curr = [[[NSString alloc] initWithFormat:@"http://xyz.com", [[retrievedArray objectAtIndex:selectedIndex] BookNumber]] autorelease];
    NSData* xmlData_replist = [NSData dataWithContentsOfURL:[NSURL URLWithString:urlstr_replist_curr] ];
    replist_rptdt_dict = (NSMutableDictionary *)PerformXMLXPathQuery(xmlData_replist, @"//XX/YY[@RD]"); 
    replist_rpttype_dict = (NSMutableDictionary *)PerformXMLXPathQuery(xmlData_replist, @"//XX/YY[@RT='A']"); 

    NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init]  autorelease];
    [dateFormatter setDateFormat:@"YYYY"];
    NSDate *date = [NSDate date];
    int tmpCurrYearInt = [[dateFormatter stringFromDate:date] intValue];

    NSString *tmpRptDt;
    NSMutableArray *tempArrDt;

    for (NSDictionary *period in replist_rpttype_dict){
        for (NSDictionary *nodeAttributeArray in [period objectForKey:@"nodeAttributeArray"]){
            NSString *tmpAttrName = [nodeAttributeArray objectForKey:@"attributeName"];

            if ([tmpAttrName isEqualToString:@"ReportDate"]) {
                tmpRptDt = [nodeAttributeArray objectForKey:@"nodeContent"];

                tempArrDt = (NSMutableArray *)[tmpRptDt componentsSeparatedByString:@"-"];
                tmpYrVal = [[tempArrDt lastObject] intValue];

                if (tmpYrVal == tmpCurrYearInt) {
                    self.curr_rep_date = [NSString stringWithFormat:@"%d", tmpRptDt];
                }
                else if (tmpYrVal == (tmpCurrYearInt-1)) {
                    self.curr_rep_date = (NSMutableString *)[tmpRptDt stringByReplacingOccurrencesOfString:[NSString stringWithFormat:@"%d",tmpYrVal] withString:[NSString stringWithFormat:@"%d",(tmpCurrYearInt-1)]];
                }
                else if (tmpYrVal == (tmpCurrYearInt-2)) {
                    self.curr_rep_date = (NSMutableString *)[tmpRptDt stringByReplacingOccurrencesOfString:[NSString stringWithFormat:@"%d",tmpYrVal] withString:[NSString stringWithFormat:@"%d",(tmpCurrYearInt-2)]];
                }
                else {
                    parse_error_str = [NSMutableString stringWithString:@"Report error"];
                }

            }
        }
    }
    NSLog(@"tmpRptDt is %@, Curr Rep date is %@",tmpRptDt, self.curr_rep_date);

    [urlstr_replist_curr release];

    [tableView reloadData];
}

在dealloc中，我正在釋放；

[parse_error_str release];
    [replist_rptdt_dict release];
    [replist_rpttype_dict release];
    [curr_rep_date release];
    [aBook release];
    [tableView release];

Answer 1

如果您curr_rep_date屬性被聲明為retain或copy ，那么這是一個泄漏：

self.curr_rep_date = [[NSMutableString alloc] init];

+alloc將返回您擁有的實例，並且該屬性還將聲明所有權（通過將retain發送到數組）。

您應該這樣做：

self.curr_rep_date = [NSMutableString string];

另外，執行以下操作：

tempArrDt = (NSMutableArray *)[tmpRptDt componentsSeparatedByString:@"-"];

要么

self.curr_rep_date = (NSMutableString *)[tmpRptDt stringByReplacingOccurrencesOfString:[NSString stringWithFormat:@"%d",tmpYrVal] withString:[NSString stringWithFormat:@"%d",(tmpCurrYearInt-1)]];

完全錯了。 強制轉換實際上不會更改對象的類型。 它只是關閉編譯器。 因此， -componentsSeparatedByString:將始終返回不可變數組，即使將其NSMutableArray轉換為NSMutableArray （或其他任何東西）也是如此。 注意返回類型。