检查数据库|| 复制数据库文件

//检查数据库|| 复制数据库文件

    NSArray *searchPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *folderPath = [searchPaths objectAtIndex:0];
    NSString *dbfilePath = [folderPath stringByAppendingPathComponent:DB_FILE_NAME];
    if (![[NSFileManager defaultManager] fileExistsAtPath:dbfilePath]) {
        //don't find db, need to copy
        NSString *backDbPath = [[NSBundle mainBundle] pathForResource:DB_SOURCE_NAME ofType:DB_SOURCE_TYPE];
        if (!backDbPath) {
            NSLog(@"cannot find backup db to copy, bail");
        } else {
            BOOL copyBackDB = [[NSFileManager defaultManager] copyItemAtPath:backDbPath toPath:dbfilePath error:nil];
            if (!copyBackDB) {
                NSLog(@"copying backup db failed, bail");
            }
        }
    }

#define DB_FILE_NAME @"gtalk.db"
#define DB_SOURCE_NAME @"gtalk"
#define DB_SOURCE_TYPE @"db"