UITextField category to handle selections with NSRanges. Adds methods to get an NSRange representing the current selection and to select a range of characters with an NSRange.

UITextField+SelectionRanges.h

//
//  UITextField+SelectionRanges.h
//  Kitchen Unit Converter
//
//  Created by Anthony Mattox on 1/5/13.
//  Copyright (c) 2013 Friends of The Web. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface UITextField (SelectionRanges)

- (NSRange) selectionRange;
- (void) selectRange:(NSRange) range;

@end

UITextField+SelectionRanges.m

//
//  UITextField+SelectionRanges.m
//  Kitchen Unit Converter
//
//  Created by Anthony Mattox on 1/5/13.
//  Copyright (c) 2013 Friends of The Web. All rights reserved.
//

#import "UITextField+SelectionRanges.h"

@implementation UITextField (SelectionRanges)

- (NSRange) selectionRange {
    return NSMakeRange([self offsetFromPosition:self.beginningOfDocument toPosition:self.selectedTextRange.start], [self offsetFromPosition:self.selectedTextRange.start toPosition:self.selectedTextRange.end]);
}

- (void) selectRange:(NSRange) range {
    UITextPosition *startPosition = [self positionFromPosition:self.beginningOfDocument offset:range.location];
    UITextPosition *endPosition = [self positionFromPosition:self.beginningOfDocument offset:range.location+range.length];
    self.selectedTextRange = [self textRangeFromPosition:startPosition toPosition:endPosition];
}

@end

That's pretty useful. Thanks a lot !

awesome