Question

当我在iPhone模拟器上运行我的第一个“sqlite”应用程序时，我收到此错误。 xcode没有问题，但是当我点击我的应用程序时，它会在调试窗口中抛出错误。我已经在这里放置了所有必要的代码，请帮助我连接“sqlite”并删除这些错误。

错误如下：

Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<ViewController 0x8a45930> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key departmentbox.'
*** First throw call stack:
(0x2091012 0x119ee7e 0x2119fb1 0xc4b711 0xbccec8 0xbcc9b7 0xbf7428 0x3030cc 0x11b2663 0x208c45a 0x301bcf 0x1c6e37 0x1c7418 0x1c7648 0x1c7882 0x116a25 0x116dbf 0x116f55 0x11ff67 0xe3fcc 0xe4fab 0xf6315 0xf724b 0xe8cf8 0x1fecdf9 0x1fecad0 0x2006bf5 0x2006962 0x2037bb6 0x2036f44 0x2036e1b 0xe47da 0xe665c 0x233d 0x2265)
libc++abi.dylib: terminate called throwing an exception
(lldb)

DBManager.m：

//
//  DBManager.m
//  sqlite
//
//  Created by Techinfiniti on 14/05/14.
//  Copyright (c) 2014 Techinfiniti. All rights reserved.
//

#import "DBManager.h"
#import <sqlite3.h>

static DBManager *sharedInstance = nil;
static sqlite3 *database = nil;
static sqlite3_stmt *statement = nil;



@implementation DBManager

+(DBManager*)getSharedInstance{

    if(!sharedInstance){
        sharedInstance = [[super allocWithZone:NULL]init];
        [sharedInstance createDB];
    }
    return sharedInstance;
}

-(BOOL)createDB{

    NSString *docsDir;
    NSArray *dirPaths;

        dirPaths = NSSearchPathForDirectoriesInDomains(NSDocumentationDirectory, NSUserDomainMask, YES);
    docsDir = dirPaths[0];
    databasePath = [[NSString alloc] initWithString:[docsDir stringByAppendingPathComponent:@"student.db"]];
    BOOL isSuccess = YES;
    NSFileManager *filemgr = [NSFileManager defaultManager];

    if([filemgr fileExistsAtPath:databasePath]== NO)
    {
        const char *dbpath = [databasePath UTF8String];
        if(sqlite3_open(dbpath,&database)== SQLITE_OK )
        {
            char *errMsg;
            const char *sql_stmt = "create table if not exists studentsDetail (regno integer primary key, name text, department text, year text)";

            if(sqlite3_exec(database,sql_stmt,NULL,NULL,&errMsg)!= SQLITE_OK)
            {

                isSuccess = NO;
                NSLog(@"failed to open create table");
            }
            sqlite3_close(database);
            return isSuccess;
        }
        else{
            isSuccess = NO;
            NSLog(@"Failed to open/create database");
        }
    }return isSuccess;

}

-(BOOL)saveData:(NSString*)registerNumber name:(NSString*)name
     department:(NSString *)department year:(NSString *)year;
{
    const char *dbpath = [databasePath UTF8String];
    if(sqlite3_open(dbpath,&database)== SQLITE_OK )
    {
        NSString *insertSQL = [NSString stringWithFormat:@"insert into studentDetail(regno,name,department,year)values(\"%d\",\"%@\",\"%@\",\"%@\")",[registerNumber integerValue],name,department,year];
        const char *insert_stmt = [insertSQL UTF8String]; sqlite3_prepare_v2(database, insert_stmt,-1,&statement,NULL);



    if(sqlite3_step(statement) == SQLITE_DONE)
{
    return YES;
}
else{
    return NO;
}
sqlite3_reset(statement);
}
return NO;

}

-(NSArray*) findByRegisterNumber:(NSString *)registerNumber
{

    const char *dbpath = [databasePath UTF8String];
    if(sqlite3_open(dbpath,&database)== SQLITE_OK)
    {
        NSString *querySQL = [NSString stringWithFormat:@"select name, department,year from studentDetail where regno=\"%@\"",registerNumber];

        const char *query_stmt = [querySQL UTF8String];
        NSMutableArray *resultArray = [[NSMutableArray alloc]init];
        if(sqlite3_prepare_v2(database,query_stmt,-1,&statement,NULL)== SQLITE_OK)
        {
            if(sqlite3_step(statement) == SQLITE_ROW)
            {
                NSString *name = [[NSString alloc] initWithUTF8String:(const char *) sqlite3_column_text(statement, 0)];
                [resultArray addObject:name];

                NSString *department = [[NSString alloc]initWithUTF8String:(const char*) sqlite3_column_text(statement,1)];
                [resultArray addObject:department];
                return resultArray;

                 NSString *year = [[NSString alloc]initWithUTF8String:(const char*) sqlite3_column_text(statement,2)];
                [resultArray addObject:year];
                return resultArray;


            }
            else{
                NSLog(@"Not Found");
                return nil;
            }
            sqlite3_reset(statement);
        }

    }
    return nil;
}

@end

ViewController.h：

//
//  ViewController.h
//  sqlite
//
//  Created by Techinfiniti on 14/05/14.
//  Copyright (c) 2014 Techinfiniti. All rights reserved.
//

#import <UIKit/UIKit.h>
#import "DBManager.h"

@interface ViewController : UIViewController<UITextFieldDelegate>
{
    IBOutlet UITextField *regNoTextField;
    IBOutlet UITextField *nameTextField;
    IBOutlet UITextField *departmentTextField;
    IBOutlet UITextField *yearTextField;
    IBOutlet UITextField *findByRegisterNumberTextField;
    IBOutlet UIScrollView *myScrollView;
}

-(IBAction)saveData:(id)sender;
-(IBAction)findData:(id)sender;


/*
- (IBAction)find:(id)sender;

- (IBAction)save:(id)sender;


@property (weak, nonatomic) IBOutlet UITextField *findbox;

@property (weak, nonatomic) IBOutlet UITextField *regnobox;

@property (weak, nonatomic) IBOutlet UITextField *namebox;

@property (weak, nonatomic) IBOutlet UITextField *departmentbox;

@property (weak, nonatomic) IBOutlet UITextField *year;
*/

@end

ViewController.m：

//
//  ViewController.m
//  sqlite
//
//  Created by Techinfiniti on 14/05/14.
//  Copyright (c) 2014 Techinfiniti. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{

    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];

    if(self)
    {


    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

/*
- (IBAction)find:(id)sender {
}

- (IBAction)save:(id)sender {
}

 */

-(IBAction)saveData:(id)sender{
    BOOL success = NO;
    NSString *alertString = @"Data Insertion falied";
    if(regNoTextField.text.length>0 && yearTextField.text.length>0 && departmentTextField.text.length>0 && yearTextField.text.length>0)
    {

        success = [[DBManager getSharedInstance]saveData:regNoTextField.text name:nameTextField.text department:departmentTextField.text year:yearTextField.text];
    }
    else
    {
        alertString = @"Enter all fields";
    }

    if(success == NO)
    {

        UIAlertView *alert = [[UIAlertView alloc]initWithTitle:alertString message:nil delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alert show];
    }

}

-(IBAction)findData:(id)sender{

    NSArray *data = [[DBManager getSharedInstance]findByRegisterNumber:findByRegisterNumberTextField.text];

    if(data == nil)
    {

        UIAlertView *alert = [[UIAlertView alloc]initWithTitle:
                              @"Data Not Found" message:nil delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alert show];
        regNoTextField.text = @"";
        nameTextField.text = @"";
        departmentTextField.text = @"";
        yearTextField.text = @"";

    }
    else{

        regNoTextField.text = findByRegisterNumberTextField.text;
        nameTextField.text = [data objectAtIndex:0];
        departmentTextField.text = [data objectAtIndex:1];
        yearTextField.text = [data objectAtIndex:2];
    }


}


#pragma mark - Text field delegate

-(void)textFieldDidBeginEditing:(UITextField *)textField{

    [myScrollView setFrame:CGRectMake(10,50,300,200)];

}

-(BOOL) textFieldShouldReturn:(UITextField *)textField
{

    [textField resignFirstResponder];
    return YES;
}
@end

Answer 1

您在departmentbox上未使用departmentTextField属性ViewController，但您没有从故事板中删除departmentbox，

转到您的连接检查器并删除未使用的密钥department box，然后构建您的应用

enter image description here

此处department box显示在Reference Outlet刚删除department box并构建您的应用

Answer 2

您已将IB中的UITextField与“departmentbox”相关联。

@property (weak, nonatomic) IBOutlet UITextField *departmentbox;

但后来您在视图控制器中评论了上述行。

当您尝试运行应用程序时，IB正在查看viewcontroller中的“departmentbox”。这导致了崩溃。

断开IB中的“部门框”将解决问题。

Answer 3

那是因为您在departmentbox上将属性departmentTextField重命名为ViewController，但显然忘了更新故事板

此外，如果您不需要在.h文件中公开您的商店，则无需使用ivars，声明私有财产：

在.m声明

中

@interface UIViewController ()
@property (nonatomic, weak) IBOutlet UITextField *regNoTextField;
// etc
@end

Answer 4

当xib文件中存在未知属性时，通常会出现此错误。

如果在xib关联后重命名属性，可能会发生这种情况。

此处，关联媒体资源为 departmentbox ，但重命名为 departmentTextField

Answer 5

也许你已经在视图控制器中声明了一个名为“departmentbox”的iVar，在xib文件中创建了一个到iVar的连接，稍后你删除/重命名了这个iVar但是忘了删除在xib文件中创建的连接。您可以检查视图控制器类的xib文件，看看是否与departmentBox有任何连接。如果你看到了（在xib的插座连接右侧显示了一个小警告图标），只需删除该连接就可以了。

＆＃39; NSUnknownKeyException＆＃39;，原因：＆＃39; [<viewcontroller 0x8a45930 =“”> setValue：forUndefinedKey：]：</viewcontroller>

5 个答案: