How to convert NSNumber to NSString

问题:

So I have an NSArray "myArray" with NSNumbers and NSStrings. I need them in another UIView so i go like this:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {

DetailViewController *details = [[DetailViewController alloc] initWithNibName:@"DetailView" bundle:nil];
details.subjectText = [[myArray objectAtIndex:indexPath.row] objectForKey:@"subject"];

The subjectText works. But how can I get the NSNumbers out of it? (I actually need them as strings...) I would convert a NSString out of a NSNumber like this: NSString *blah = [NSNumber intValue]. But I don't know how to set it up in the code above...

回答1:

Try:

NSString *myString = [NSNumber stringValue];

回答2:

You can do it with:

NSNumber *myNumber = @15;
NSString *myNumberInString = [myNumber stringValue];

回答3:

//An example of implementation :
// we set the score of one player to a value
[Game getCurrent].scorePlayer1 = [NSNumber numberWithInteger:1];
// We copy the value in a NSNumber
NSNumber *aNumber = [Game getCurrent].scorePlayer1;
// Conversion of the NSNumber aNumber to a String with stringValue
NSString *StringScorePlayer1 = [aNumber stringValue];

回答4:

or try NSString *string = [NSString stringWithFormat:@"%d", [NSNumber intValue], nil];

回答5:

The funny thing is that NSNumber converts to string automatically if it becomes a part of a string. I don't think it is documented. Try these:

NSLog(@"My integer NSNumber:%@",[NSNumber numberWithInt:184]);
NSLog(@"My float NSNumber:%@",[NSNumber numberWithFloat:12.23f]);
NSLog(@"My bool(YES) NSNumber:%@",[NSNumber numberWithBool:YES]);
NSLog(@"My bool(NO) NSNumber:%@",[NSNumber numberWithBool:NO]);

NSString *myStringWithNumbers = [NSString stringWithFormat:@"Int:%@, Float:%@ Bool:%@",[NSNumber numberWithInt:132],[NSNumber numberWithFloat:-4.823f],[NSNumber numberWithBool:YES]];
NSLog(@"%@",myStringWithNumbers);

It will print:

My integer NSNumber:184
My float NSNumber:12.23
My bool(YES) NSNumber:1
My bool(NO) NSNumber:0
Int:132, Float:-4.823 Bool:1

Works on both Mac and iOS

This one does not work:

NSString *myNSNumber2 = [NSNumber numberWithFloat:-34512.23f];

回答6:

In Swift you can do like this

let number : NSNumber = 95
let str : String = number.stringValue

回答7:

In Swift 3.0

let number:NSNumber = 25
let strValue = String(describing: number as NSNumber)
print("As String => \(strValue)")

We can get the number value in String.