nsnumber into uipasteboard

Question

I'd like to copy a float into the pasteboard, but the important thing is the value, as I want to paste it later in numbers, as a number.

Tried with :

[pasteboard setValue:SomeNSNumberWhereIStoredTheFloat forPasteboardType:@"NSNumber"];

With that, it got nothing to paste, and with pasteboard.string = numberInStringValue, it pastes the number as a series of characters, in what I'm not interested.

Thanks for your help

score 2 · Answer 1 · answered Aug 11 '12 at 01:27

The "type" of pasteboard data is not the name of a class, it's a Uniform Type Identifier (UTI, or just UT if you remember what else UTI stands for.) In this case, your data does not have an associated UTI (numbers are abstract concepts, not data formats.) You'll have to figure out the best way to store that number and retrieve it.

I think in this case, formatting the number into a string will suffice:

NSString *numString = [NSString stringWithFormat:@"%f", theFloatValue];
pasteboard.string = numString;

And later, when getting it back:

float theFloatValue2 = [pasteboard.string doubleValue];

This does not take into account checking for nil or other error handling.

If you need very high precision, you may need to investigate an NSData-based storage technique.

It's what I tried, but I'd need to paste the number into a numbers sheet, treating it as a number. That's whay pasteboard.string doesn't work for me, I can't get it back later. Thanks anyway! — g10k, Aug 11 '12 at 01:32

score 0 · Answer 2 · edited May 23 '17 at 12:24

You can store an NSNumber directly. You can used the following methods from the API

setValue:forPasteboardType:

Use this method to put an object on the pasteboard that is a standard property-list object that is an object of the NSString, NSArray, NSDictionary, NSDate, NSNumber, or NSURL class.

valueForPasteboardType:

This method attempts to return an object that is of a class type appropriate to the representation type, which typically is a UTI. For example, if the representation type is kUTTypePlainText (public.plain-text), the method returns an NSString object. If the method cannot determine the class type from the representation type, it returns the object as a generic property-list object. Property-list objects include NSString, NSArray, NSDictionary, NSDate, or NSNumber objects, with NSURL objects also as a possibility. If the method cannot decode the value as a property-list object, it returns the pasteboard item as an NSData object.

The real problem comes in finding the correct UTI so the class will automatically give you back an NSNumber and not give you back an NSData object instead.

To make matters worse, the code doest not appear to work as the advertised by the documentation. I've heard from several people the method will always return you NSData. You can find an example (and a workaround) of such issue in this answer.

score 0 · Answer 3 · answered Apr 22 '14 at 07:24

You can store your float value as NSNumber. But NSNumber is not stored in UIPasteboard correctly although docs states it does (bug?).

To keep NSNumber in UIPasteboard you should archive NSNumber to NSData, and to retrieve NSNumber from UIPasteboard you should unarchive NSData back to NSNumber.

// adding data to pasteboard
NSNumber *number = [NSNumber numberWithDouble:floatValue]; // store your value here
NSData *data = [NSKeyedArchiver archivedDataWithRootObject:number]; // archive NSNumber to NSData
NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:data, @"yourKey",nil];
[[UIPasteboard generalPasteboard] addItems:[NSArray arrayWithObject:dict]];

// retrieving data
NSData *data = [dict valueForKey:@"yourKey"]; // here dict is properly obtained NSDictionary of pasteboard object
NSNumber *number = [NSKeyedUnarchiver unarchiveObjectWithData:data]; // unarchive NSData to NSNumber

nsnumber into uipasteboard

3 Answers3