2016-02-10 12:35:14.524 FlightTableView[2448:127703] *** Assertion failure in -[AppDelegate copyDatabaseIfNeeded], /Volumes/Data/Nasrin/FlightTableView/FlightTableView/AppDelegate.m:30
2016-02-10 12:35:14.528 FlightTableView[2448:127703] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Failed to create writable database file with message 'The file “Airports.sqlite3” couldn’t be opened because there is no such file.'.'
*** First throw call stack:
(
0 CoreFoundation 0x00000001026c1e65 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x0000000102138deb objc_exception_throw + 48
2 CoreFoundation 0x00000001026c1cca +[NSException raise:format:arguments:] + 106
3 Foundation 0x0000000101d844de -[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:] + 198
4 FlightTableView 0x0000000101b1529c -[AppDelegate copyDatabaseIfNeeded] + 668
5 FlightTableView 0x0000000101b15439 -[AppDelegate application:didFinishLaunchingWithOptions:] + 89
6 UIKit 0x0000000102a661f1 -[UIApplication _handleDelegateCallbacksWithOptions:isSuspended:restoreState:] + 272
7 UIKit 0x0000000102a67397 -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 3415
8 UIKit 0x0000000102a6dcc6 -[UIApplication _runWithMainScene:transitionContext:completion:] + 1760
9 UIKit 0x0000000102a6ae7b -[UIApplication workspaceDidEndTransaction:] + 188
10 FrontBoardServices 0x000000010535c754 -[FBSSerialQueue _performNext] + 192
11 FrontBoardServices 0x000000010535cac2 -[FBSSerialQueue _performNextFromRunLoopSource] + 45
12 CoreFoundation 0x00000001025eda31 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
13 CoreFoundation 0x00000001025e395c __CFRunLoopDoSources0 + 556
14 CoreFoundation 0x00000001025e2e13 __CFRunLoopRun + 867
15 CoreFoundation 0x00000001025e2828 CFRunLoopRunSpecific + 488
16 UIKit 0x0000000102a6a7cd -[UIApplication _run] + 402
17 UIKit 0x0000000102a6f610 UIApplicationMain + 171
18 FlightTableView 0x0000000101b18acf main + 111
19 libdyld.dylib 0x00000001040b992d start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
（void）copyDatabaseIfNeeded方法如下。
NSFileManager *fileManager = [NSFileManager defaultManager];
NSError *error; NSString *dbPath = [self getDBPath];
BOOL success = [fileManager fileExistsAtPath:dbPath];
if(!success)
{
NSString *defaultDBPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"Airports.sqlite"];
success = [fileManager copyItemAtPath:defaultDBPath toPath:dbPath error:&error];
if (!success) NSAssert1(0, @"Failed to create writable database file with message '%@'.", [error localizedDescription]);