代碼繞過數組創建從sqlite數據庫循環

Question

我的NSMutableArray創建代碼由於某種原因被完全繞過。理論上它應該創建一個基於sqlite數據庫的NSMutableArray。只有一個警告消息，沒有錯誤。我錯過了什麼？ 實現文件是：礦山

#import "iProspectFresno LiteAppDelegate.h" 
#import "MainViewController.h" 
#import "Mine.h" 
#import <Foundation/Foundation.h> 
@implementation iProspectFresno_LiteAppDelegate 
@synthesize window; 
@synthesize mainViewController; 
@synthesize mines; 
-(void) checkAndCreateDatabase { 
    BOOL success; 
NSFileManager *fileManager = [NSFileManager defaultManager]; 
success = [fileManager fileExistsAtPath:databasePath]; 
if(success) return; 
NSString *databasePathFromApp = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:databaseName]; 
[fileManager copyItemAtPath:databasePathFromApp toPath:databasePath error:nil]; 
} 
-(void) readMinesFromDatabase 
{ 
sqlite3 *database; 
mines = [[NSMutableArray alloc] init]; 
NSLog(@"readMinesFromDatabase initialized"); 
if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) { 
    const char *sqlStatement = "select * from MinesoftheMotherLode"; 
    sqlite3_stmt *compiledStatement; 
    NSLog(@"first if statement"); 
    if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) 
    { 
    NSLog(@" second if statement initialized"); 
    while(sqlite3_step(compiledStatement) == SQLITE_ROW) 
    { 
    NSNumber *aentryNumber = [NSNumber numberWithInt:(int)sqlite3_column_int(compiledStatement, 1)]; 
    NSString *amineName = [NSString stringWithUTF8String:(char*)sqlite3_column_text(compiledStatement, 2)]; 
    NSString *amineType = [NSString stringWithUTF8String:(char*)sqlite3_column_text(compiledStatement, 3)]; 
    NSString *astatus = [NSString stringWithUTF8String:(char*)sqlite3_column_text(compiledStatement, 4)]; 
    NSNumber *alatitude = [NSNumber numberWithDouble:(double)sqlite3_column_double(compiledStatement, 5)]; 
    NSNumber *alongitude = [NSNumber numberWithDouble:(double)sqlite3_column_double(compiledStatement, 6)]; 
    NSString *ametal =[NSString stringWithUTF8String:(char*)sqlite3_column_text(compiledStatement, 7)]; 
    BOOL *adisplay = NO; 
    NSNumber *acoverRegion =[NSNumber numberWithInt:(int)sqlite3_column_int(compiledStatement, 9)]; 
    NSLog(@"mine", aentryNumber, amineName, amineType, astatus, alatitude, alongitude, ametal, adisplay, acoverRegion); 
    Mine *mine = [[Mine alloc] initWithEntryNumber:aentryNumber mineName:amineName mineType:amineType status:astatus latitudeInitial:alatitude longitudeInitial:alongitude metal:ametal display:adisplay coverRegion:acoverRegion]; 
    [mines addobject:mine]; 
    [mine release]; 
    } 
} 
    NSLog(@"created database successfully"); 
    sqlite3_finalize(compiledStatement); 
} 
sqlite3_close(database); 
    } 
- (void)applicationDidFinishLaunching:(UIApplication *)application { 
    databaseName = @"MinesoftheMotherLode.sql"; 
    NSArray *documentPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
NSString *documentsDir = [documentPaths objectAtIndex:0]; 
databasePath = [documentsDir stringByAppendingPathComponent:databaseName]; 
[self checkAndCreateDatabase]; 
[self readMinesFromDatabase]; 
MainViewController *aController = [[MainViewController alloc] initWithNibName:@"MainView" bundle:nil]; 
self.mainViewController = aController; 
[aController release]; 
    mainViewController.view.frame = [UIScreen mainScreen].applicationFrame; 
[window addSubview:[mainViewController view]]; 
    [window makeKeyAndVisible]; 
} 

實現文件是在這裏：

#import "Mine.h" 
@implementation Mine 
@synthesize entryNumber, mineName, mineType, status, latitudeInitial, longitudeInitial, metal, display, coverRegion; 
-(id)initWithEntryNumber:(NSNumber *)e mineName:(NSString *)n mineType:(NSString *)t status:(NSString *)s latitudeInitial:(NSNumber *)l longitudeInitial:(NSNumber *)o metal:(NSString *)m display:(BOOL *)d coverRegion:(NSNumber *)c 
{ 
self.entryNumber = e; 
self.mineName = n; 
self.mineType = t; 
self.status = s; 
self.latitudeInitial = l; 
self.longitudeInitial = o; 
self.metal = m; 
self.display = d; 
self.coverRegion = c; 
return self; 
} 
@end 

的NSLog的「第二if語句初始化」沒有顯示在控制檯上的。關於需要在這裏修正什麼的任何想法？是的，我知道，我應該使用核心數據。

Answer 1

看來你已經回答了關於它加載的最初問題。您就有關空字符串的二次碰撞的問題，您應該是裝載這樣的字符串：

if (sqlite3_column_text(init_statement, 0) != NULL) { 
    self.someString = [NSString stringWithUTF8String:(char *)sqlite3_column_text(init_statement, 0)]; 
} else { 
    self.someString = @""; 
}