Can NSUserdefaults save two arrays of same name

问题:

Can NSUserdefault save two arrays of same name or it replaces previous array?

回答1:

yes it replace with same variable and xcode not allowed to duplicate the same name of any object in same class so your application not compile until you not remove any one array name from class...

Update:-

In AppDelegate.h file just declare variable...

NSUserDefaults  *userDefaults;
NSMutableArray *yourArray;

after...

In AppDelegate.m Fille in applicationDidFinishLonching: Method

userDefaults = [NSUserDefaults standardUserDefaults];
    NSData *dataRepresentingtblArrayForSearch = [userDefaults objectForKey:@"yourArray"];
    if (dataRepresentingtblArrayForSearch != nil) {
        NSArray *oldSavedArray = [NSKeyedUnarchiverunarchiveObjectWithData:dataRepresentingtblArrayForSearch];
        if (oldSavedArray != nil)
            yourArray = [[NSMutableArray alloc]initWithArray:oldSavedArray];
        else
            yourArray = [[NSMutableArray alloc] init];
    } else {
        yourArray = [[NSMutableArray alloc] init];
    }
    [yourArray retain];

after that when you want to insert,update or delete Data from this userDefaults Use Bellow Code...

For Delete record use bellow        

[appDelegate.yourArray removeObjectAtIndex:IndexValue];// define integer value here on IndexValue

         or     for insert record use bellow..

       

[appDelegate.yourArray addObject:AddValueHere];

or for replace whole array with new array then write this

appDelegate.yourArray = YourNewArray; 

[appDelegate.yourArray retain];

after that for save whole your data synchronize NSUserDefaults like bellow...         

NSData *data=[NSKeyedArchiverarchivedDataWithRootObject:appDelegate.yourArray];
    [appDelegate.userDefaults setObject:data forKey:@"yourArray"];
    [appDelegate.userDefaults synchronize];