核心数据整数更改值？ [英] Core Data Integer changing value?

问题描述

我有一个核心数据存储整数的问题（我选择int16，因为他们有最多6个迹象）。

我的模型保存

 实体：'费用'
所讨论的属性是：
 
 
 @property保留）NSNumber *月; 
 

它由Xcode自动实现为NSNumber（Editor> createManagedmodelsubclass）

月份每个月都有一个简短的标识符。示例

  201203 //将是2012年3月
  

我使用此代码段存储新实体：

  [newExpense setValue：monthNumber forKey ：@月]; 
  

我通过抓取方法检索对象，并将它们存储在一个名为 allExpenses 。

现在我这样做：

  NSMutableArray * thisMonthExpenses = [[NSMutableArray alloc] init]; 
 
 for（Expense * entity in allExpenses）{
 int tempMonth = [[entity month] intValue]; 
 if（tempMonth == month）{
 [thisMonthExpenses addObject：entity]; 
 
} 
} 
  

过滤出正确的实体属于当前月份。

  month //是一个保存编码月份的整数（再次：正确！）
  

但不知何故代码：

  int tempMonth = [[entity month] intValue]; 
  

不会返回201203，而是错误的4595（总是相同的值）。

与此代码相同：

  for（Expense * entity in monthExpenses）{
 if（[entity day] .intValue == todayNumber.intValue）{//这里ENTITY DAY.INTVALUE返回一个完全错误的整数！ 
 [thisDayExpenses addObject：entity]; 
} 
} 
  

我似乎缺少一些东西 -

任何想法？

201203是0x311F3，而4595是0x11F3 - 所以发生的是，你丢失了最高有效字节。它听起来像在CoreData你的数字设置为16位整数，它不能存储你想要的数字（16位只能表示到十进制的低五位数）。它应该是一个32位整数。

i have a problem with core data storing integer (i chose int16 because they have a maximum of 6 signs).

my model holds

Entity: 'Expense'
the attribute in question is:


@property (nonatomic, retain) NSNumber * month;

it was automatically implemented as NSNumber by Xcode (Editor > createManagedmodelsubclass)

month holds an short identifier for every month. example

201203     //would be march of 2012

i store new entities with this snippet:

[newExpense setValue:monthNumber forKey:@"month"];

which works just fine. monthNumber has always the right value before i store it.

i retrieve objects with a fetching method and store them in an array called allExpenses. the array count is true and i have the right amount of entities in it.

now i do this:

NSMutableArray *thisMonthExpenses = [[NSMutableArray alloc]init ];

for (Expense *entity in allExpenses) {
    int tempMonth = [[entity month]intValue];
    if (tempMonth == month) {
        [thisMonthExpenses addObject:entity];

    }
}

to filter out the right entities that belong to the current month.

month // is an integer that holds the encoded month (again: correctly!)

but somehow the code:

int tempMonth = [[entity month]intValue];

does not return 201203, but strangly 4595 (always the same value).

the same happens with this code:

for (Expense *entity in monthExpenses) {
    if ([entity day].intValue == todayNumber.intValue) { //HERE ENTITY DAY.INTVALUE RETURNS A COMPLETELY WRONG INTEGER!
        [thisDayExpenses addObject:entity];
    }
}

i seem to be missing something - but i cannot figure out what, i tried around for 2 hours now and always get the wrong int value after reading my entities..

any ideas?

解决方案

201203 is 0x311F3, while 4595 is 0x11F3 — so what's happening is, you're losing the most significant byte. It sounds like in CoreData you have the number set as a 16-bit integer, which isn't capable of storing the number you want (16 bits can only represent up to the low five digits in decimal). It should be a 32-bit integer.

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