assume the following:
@interface BOOK : NSObject
{
@private
NSString *title;
NSString *author;
NSString *ISBN;
}
...
BOOK *booklist = [[[BOOK alloc] init] autorelease];
NSMutableArray *myarray = [NSMutableArray array];
while (true)
{
booklist.title = @"title";
booklist.author = @"author";
booklist.ISBN = @"1234-1";
[myarray addObject:booklist];
}
my question is how do I retrieve object of BOOK i.e booklist.title, .author, .ISBN at a certain index in myarray.
with this code? Impossible, because you add the same bookList for the rest of the time (until there is no more memory)
With code without infinite loops you would use
NSInteger index = 0;
Book *aBook = [myArray objectAtIndex:index];
NSString *title = aBook.title;
Starting with Xcode 4.5 (and Clang 3.3), you may use Objective-C Literals:
Book *firstBookInArray = myArray[0];
This may not help at all, but I remember having trouble when not casting while pulling objects out of arrays...
Book *aBook = (Book *)[myArray objectAtIndex: index];
It may help, may not...and I know this post is old, but maybe it'll help someone..
.scott
You have this extends if you want
Create file extends.h add this code and #import "extends.h" in your project :
/*______________________________ Extends NSMutableArray ______________________________*/
/**
* Extend NSMutableArray
* By DaRkD0G
*/
@interface NSMutableArray (NSArrayAdd)
/**
* Get element at index
*
* @param index
*/
- (NSObject *) getAt:(int) index;
@end
/**
* Extend NSMutableArray Method
* By DaRkD0G
*/
@implementation NSMutableArray (NSArrayAdd)
/**
* Get element at index
*
* @param index
*/
- (NSObject *) getAt:(int) index {
NSInteger anIndex = index;
NSObject *object = [self objectAtIndex:anIndex];
if (object == [NSNull null]) {
return nil;
} else {
NSLog(@"OK found ");
return object;
}
}
@end
/*______________________________ Extends NSArray ______________________________*/
/**
* Extend NSArray
* By DaRkD0G
*/
@interface NSArray (NSArrayAdd)
/**
* Get element at index
*
* @param index
*/
- (NSObject *) getAt:(int) index;
@end
/**
* Extend NSArray Method
* By DaRkD0G
*/
@implementation NSArray (NSArrayAdd)
/**
* Get element at index
*
* @param index
*/
- (NSObject *) getAt:(int) index {
NSInteger anIndex = index;
NSObject *object = [self objectAtIndex:anIndex];
if (object == [NSNull null]) {
return nil;
} else {
NSLog(@"OK found ");
return object;
}
}
@end
USE :
NSObject object = [self.arrayItem getAt:0];
NSObject object2 = [self.arrayItem getAt:50];
