我正在使用Swift的iOs程序，我正在使用Core Data，我试图找到如何获得自动增量ID，我发现了这个：
但这里没有问题，所以我试着看看如何编写自动增量属性：
我在名为“id”的.xcdatamodeld文件中添加了一个新属性，我在Objective-C中找到了一个解决方案：
MSBuild - Implementation notes
但我不知道如何将其解析为Swift2
我的代码：
let appDel: AppDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
let context: NSManagedObjectContext = appDel.managedObjectContext
let newDemande = NSEntityDescription.insertNewObjectForEntityForName("Demandes", inManagedObjectContext: context)
newDemande.setValue(soapRequest.xmlString, forKey: "xml")
newDemande.setValue(1, forKey: "statutenvoie")
do {
try context.save()
} catch {
print("erreur data")
}
do {
let request = NSFetchRequest(entityName: "Demandes")
let results = try context.executeFetchRequest(request)
if results.count > 0 {
for item in results as! [NSManagedObject]{
let xml = item.valueForKey("xml")
let statutenvoie = item.valueForKey("statutenvoie")
print(item.objectID)
print(xml!, statutenvoie!)
}
}
} catch {
print("erreur data")
}
UUID错误：
代码：
let appDel: AppDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
let context: NSManagedObjectContext = appDel.managedObjectContext
let newDemande = NSEntityDescription.insertNewObjectForEntityForName("Demandes", inManagedObjectContext: context)
newDemande.setValue(NSUUID().UUIDString, forKey: "id")
newDemande.setValue(soapRequest.xmlString, forKey: "xml")
newDemande.setValue(1, forKey: "statutenvoie")
do {
try context.save()
} catch {
print("erreur data")
}
do {
let request = NSFetchRequest(entityName: "Demandes")
let results = try context.executeFetchRequest(request)
if results.count > 0 {
for item in results as! [NSManagedObject]{
let id = item.valueForKey("id")
let xml = item.valueForKey("xml")
let statutenvoie = item.valueForKey("statutenvoie")
// print(item.objectID)
print(id!, xml!, statutenvoie!)
}
}
} catch {
print("erreur data")
}
错误：
2016-01-11 16:33:18.921 ...[2694:108875] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Unacceptable type of value for attribute: property = "id"; desired type = NSNumber; given type = __NSCFString; value = 781EFF10-A9F1-4710-98C1-6D342B2EB480.'
*** First throw call stack:
(
0 CoreFoundation 0x0000000110a2be65 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x00000001132f8deb objc_exception_throw + 48
2 CoreData 0x00000001105c77b0 _PFManagedObject_coerceValueForKeyWithDescription + 2864
3 CoreData 0x000000011059f621 _sharedIMPL_setvfk_core + 177
4 ... 0x000000010ff690e5 _TFC7...29DemandeGratuiteViewController7ValiderfS0_FPSs9AnyObject_T_ + 4757
5 ... 0x000000010ff6aaa6 _TToFC7...29DemandeGratuiteViewController7ValiderfS0_FPSs9AnyObject_T_ + 54
6 UIKit 0x0000000112285e73 _UIGestureRecognizerSendTargetActions + 153
7 UIKit 0x00000001122824e5 _UIGestureRecognizerSendActions + 162
8 UIKit 0x00000001122804e2 -[UIGestureRecognizer _updateGestureWithEvent:buttonEvent:] + 843
9 UIKit 0x00000001122889a0 ___UIGestureRecognizerUpdate_block_invoke904 + 79
10 UIKit 0x000000011228883e _UIGestureRecognizerRemoveObjectsFromArrayAndApplyBlocks + 342
11 UIKit 0x0000000112276101 _UIGestureRecognizerUpdate + 2634
12 UIKit 0x0000000111e0df8a -[UIWindow _sendGesturesForEvent:] + 1137
13 UIKit 0x0000000111e0f1c0 -[UIWindow sendEvent:] + 849
14 UIKit 0x0000000111dbdb66 -[UIApplication sendEvent:] + 263
15 UIKit 0x0000000111d97d97 _UIApplicationHandleEventQueue + 6844
16 CoreFoundation 0x0000000110957a31 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
17 CoreFoundation 0x000000011094d95c __CFRunLoopDoSources0 + 556
18 CoreFoundation 0x000000011094ce13 __CFRunLoopRun + 867
19 CoreFoundation 0x000000011094c828 CFRunLoopRunSpecific + 488
20 GraphicsServices 0x0000000114c2dad2 GSEventRunModal + 161
21 UIKit 0x0000000111d9d610 UIApplicationMain + 171
22 ... 0x000000010ff352cd main + 109
23 libdyld.dylib 0x0000000113e0a92d start + 1
24 ??? 0x0000000000000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
错误：
2016-01-12 09:13:03.726 ...[576:7439] CoreData: error: -addPersistentStoreWithType:SQLite configuration:(null) URL:file:///Users/informatiqueresponis/Library/Developer/CoreSimulator/Devices/314EFA4E-CC21-45A0-B3FD-FA486D52BB99/data/Containers/Data/Application/B0AB216F-D9B4-408D-ADB5-92BE2D333F62/Documents/SingleViewCoreData.sqlite options:(null) ... returned error Error Domain=NSCocoaErrorDomain Code=134100 "(null)" UserInfo={metadata={
NSPersistenceFrameworkVersion = 641;
NSStoreModelVersionHashes = {
Demandes = <e6fa8ed7 47097048 95c90274 cbc26ea7 decd6ea3 12e0df98 cd0d3cec da84d5ff>;
};
NSStoreModelVersionHashesVersion = 3;
NSStoreModelVersionIdentifiers = (
""
);
NSStoreType = SQLite;
NSStoreUUID = "7C53DEAF-C47E-446B-913E-060946C728B0";
"_NSAutoVacuumLevel" = 2;
}, reason=The model used to open the store is incompatible with the one used to create the store} with userInfo dictionary {
metadata = {
NSPersistenceFrameworkVersion = 641;
NSStoreModelVersionHashes = {
Demandes = <e6fa8ed7 47097048 95c90274 cbc26ea7 decd6ea3 12e0df98 cd0d3cec da84d5ff>;
};
NSStoreModelVersionHashesVersion = 3;
NSStoreModelVersionIdentifiers = (
""
);
NSStoreType = SQLite;
NSStoreUUID = "7C53DEAF-C47E-446B-913E-060946C728B0";
"_NSAutoVacuumLevel" = 2;
};
reason = "The model used to open the store is incompatible with the one used to create the store";
}
2016-01-12 09:13:03.730 ...[576:7439] Unresolved error Error Domain=YOUR_ERROR_DOMAIN Code=9999 "Failed to initialize the application's saved data" UserInfo={NSLocalizedDescription=Failed to initialize the application's saved data, NSLocalizedFailureReason=There was an error creating or loading the application's saved data., NSUnderlyingError=0x7fded60cdae0 {Error Domain=NSCocoaErrorDomain Code=134100 "(null)" UserInfo={metadata={
NSPersistenceFrameworkVersion = 641;
NSStoreModelVersionHashes = {
Demandes = <e6fa8ed7 47097048 95c90274 cbc26ea7 decd6ea3 12e0df98 cd0d3cec da84d5ff>;
};
NSStoreModelVersionHashesVersion = 3;
NSStoreModelVersionIdentifiers = (
""
);
NSStoreType = SQLite;
NSStoreUUID = "7C53DEAF-C47E-446B-913E-060946C728B0";
"_NSAutoVacuumLevel" = 2;
}, reason=The model used to open the store is incompatible with the one used to create the store}}}, [NSLocalizedDescription: Failed to initialize the application's saved data, NSLocalizedFailureReason: There was an error creating or loading the application's saved data., NSUnderlyingError: Error Domain=NSCocoaErrorDomain Code=134100 "(null)" UserInfo={metadata={
NSPersistenceFrameworkVersion = 641;
NSStoreModelVersionHashes = {
Demandes = <e6fa8ed7 47097048 95c90274 cbc26ea7 decd6ea3 12e0df98 cd0d3cec da84d5ff>;
};
NSStoreModelVersionHashesVersion = 3;
NSStoreModelVersionIdentifiers = (
""
);
NSStoreType = SQLite;
NSStoreUUID = "7C53DEAF-C47E-446B-913E-060946C728B0";
"_NSAutoVacuumLevel" = 2;
}, reason=The model used to open the store is incompatible with the one used to create the store}]
(lldb)
答案 0 :(得分：3)
您在评论中提供的示例仍然令人困惑。我的回答是基于我的理解，当您下次插入新条目时，您想要一个自动增加字段 - id。
如果您有两个字段，即xmlString＆amp; id。然后，首先，每次都是SortDescriptor和setFetchLimit = 1的抓取请求。如果结果为空，则插入包含id = 1的新条目。否则，请使用id = oldId + 1插入新条目。
我故意不提供任何代码，因为我不确定你真正想要的是什么。
顺便说一句，你最好使用自定义模型，即由NSManagedObject生成的XCode，而不是当前newDemande.setValue(value, forKey: "key")
修改
提供的示例代码：
// Initialize Fetch Request
let fetchRequest = NSFetchRequest(entityName: "Demandes")
// Sort Descriptor
var idDescriptor: NSSortDescriptor = NSSortDescriptor(key: "id", ascending: false)
fetchRequest.sortDescriptors = [idDescriptor] // Note this is a array, you can put multiple sort conditions if you want
// Set limit
fetchRequest.fetchLimit = 1
var newId = 0; // Default to 0, so that you can check if do catch block went wrong later
do {
let results = try self.managedObjectContext.executeFetchRequest(fetchRequest)
//Compute the id
if(results.count == 1) newId = results[0].id + 1 // slightly odd notation here, .id can be used if you use custom model. or you can use .valueForKey("id")
else newId = 1
} catch {
let fetchError = error as NSError
print(fetchError)
}
// Do the new insert afterwards
答案 1 :(得分：0)
我认为您正在发送字符串值（781EFF10-A9F1-4710-98C1-6D342B2EB480），核心数据需要NSNumber（Int）。显然，781EFF10-A9F1-4710-98C1-6D342B2EB480不是数字。
核心数据始终将Int（Doubles，Float等）值存储为NSNumber，例如：
let intValue
let intValueInNSNumber = NSNumber(int: intValue)
区别在于intValue（Int）是基本类型，而NSNumber是一个对象。
属性“id”的类型是什么？
因为，如果属性类型为“Int”，则必须将其更改为“String”，它应该可以正常工作。