SQLITE3查询目标C

-(IBAction)ButtonPressed:(id)sender 
    { 
     const char *sql = "SELECT AccessCode FROM UserAccess"; 
     NSString *sqlns; 
     sqlns = [NSString stringWithUTF8String:sql]; 
     if([Password.text isEqual:sqlns]) 
     { 
      NSLog(@"Correct"); 
     } 
      else { 
       NSLog(@"Wrong"); 
      } 

    NSLog(@"%@",sqlns); 
    }

菜鸟在这里，在的NSLog我能打印“选择AccessCode FROM UserAccess”里为let说，接入码为1234，这是我想.The挑战是要执行的命令，从而我可以检索 1234从数据库UserAcess.sqlite的表UserAccess中的列AccessCode我的数据库和表名是相同的oops。在AppDelegate中我有： ///SQLITE3查询目标C

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {  

    // Override point for customization after app launch 
    [self createEditableCopyOfDatabaseIfNeeded];  
    [window addSubview:viewController.view]; 
    [window makeKeyAndVisible]; 

    return YES; 
}

///

- (void)createEditableCopyOfDatabaseIfNeeded { 

     NSLog(@"Creating editable copy of database"); 

     // First, test for existence. 

     BOOL success; 

     NSFileManager *fileManager = [NSFileManager defaultManager]; 

     NSError *error; 

     NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 

     NSString *documentsDirectory = [paths objectAtIndex:0]; 

     NSString *writableDBPath = [documentsDirectory stringByAppendingPathComponent:@"UserAccess.sqlite"]; 

     success = [fileManager fileExistsAtPath:writableDBPath]; 

     if (success) return; 

     // The writable database does not exist, so copy the default to the appropriate location. 

     NSString *defaultDBPath = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"UserAccess.sqlite"]; 

     success = [fileManager copyItemAtPath:defaultDBPath toPath:writableDBPath error:&error]; 

     if (!success) { 

      NSAssert1(0, @"Failed to create writable database file with message '%@'.", [error localizedDescription]); 

     } 

    }

///

+(sqlite3 *) getNewDBConnection{ 

    sqlite3 *newDBconnection; 

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 

    NSString *documentsDirectory = [paths objectAtIndex:0]; 

    NSString *path = [documentsDirectory stringByAppendingPathComponent:@"UserAccess.sqlite"]; 

    // Open the database. The database was prepared outside the application. 

    if (sqlite3_open([path UTF8String], &newDBconnection) == SQLITE_OK) { 

     NSLog(@"Database Successfully Opened :) "); 

    } else { 

     NSLog(@"Error in opening database :("); 

       } 

       return newDBconnection; 

       }

请帮助:(

来源

2010-04-16 Omkar Jadhav

您应该使用Objective-C字符串常量'NSString * sqlns = @“SELECT AccessCode FROM UserAccess”;'而不是从您正在使用的C字符串中生成Objective-C字符串的复杂方法。 – 2010-04-16 06:34:41

我想NSLog中的'AccessCode'列的值（@“％@”，sqlns）; 我应该得到1234而不是：SELECT AccessCode FROM UserAccess – 2010-04-16 06:44:24

你需要做一些sqlite3调用来执行select语句并检索列值。

The sqlite3 quick start拥有一切，你需要知道这个特定的任务。

来源

2010-04-16 15:43:13 JeremyP

SQLITE3查询目标C

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