UITextField format in xx-xx-xxx

Question

I am using UITextField and i want that should take character in the format of xx-xx-xxx only numbers.

any help ?

Answer 1

Try below it will work

Objective-C

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    int groupingSize = 2;
    if([string length] == 0) {
        groupingSize = 4;
    }
    NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init] ;
    NSString *separator = @"-";
    [formatter setGroupingSeparator:separator];
    [formatter setGroupingSize:groupingSize];
    [formatter setUsesGroupingSeparator:YES];
    [formatter setSecondaryGroupingSize:2];
    if (![string  isEqual: @""] && (textField.text != nil && textField.text.length > 0)) {
        NSString *num = textField.text;
        num = [num stringByReplacingOccurrencesOfString:separator withString:@""];
        NSString *str = [formatter stringFromNumber:[NSNumber numberWithDouble:[num doubleValue]]];
        textField.text = str;
    }
    return YES;
}

Swift-3

extension ViewController: UITextFieldDelegate {

    func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
        var groupSize = 2
        let separator = "-"
        if string.characters.count == 0 {
            groupSize = 4
        }
        let formatter = NumberFormatter()
        formatter.groupingSeparator = separator
        formatter.groupingSize = groupSize
        formatter.usesGroupingSeparator = true
        formatter.secondaryGroupingSize = 2
        if var number = textField.text, string != "" {
            number = number.replacingOccurrences(of: separator, with: "")
            if let doubleVal = Double(number) {
                let requiredString = formatter.string(from: NSNumber.init(value: doubleVal))
                textField.text = requiredString
            }

        }
        return true
    }
}

Answer 2

You can call path into this method any pattern you need for your textField:

extension String {
    func applyPatternOnNumbers(pattern: String, replacmentCharacter: Character) -> String {
        var pureNumber = self.replacingOccurrences( of: "[^0-9]", with: "", options: .regularExpression)
        for index in 0 ..< pattern.count {
            guard index < pureNumber.count else { return pureNumber }
            let stringIndex = String.Index(encodedOffset: index)
            let patternCharacter = pattern[stringIndex]
            guard patternCharacter != replacmentCharacter else { continue }
            pureNumber.insert(patternCharacter, at: stringIndex)
        }
        return pureNumber
    }
}

Example:

 guard let text = textField.text else { return }
 textField.text = text.applyPatternOnNumbers(pattern: "##-##-###", replacmentCharacter: "#")

Answer 3

Had a need to do this nicely for a phone numbers with a variable format, here's what I wrote. Feel free to reuse - First I've got a method to filter a formatted string, with # being a number, and any other character being some kind of "filler" that should be conveniently inserted after the user gets to the place where it's needed.

NSMutableString *filteredPhoneStringFromStringWithFilter(NSString *string, NSString *filter)
{
    NSUInteger onOriginal = 0, onFilter = 0, onOutput = 0;
    char outputString[([filter length])];
    BOOL done = NO;

    while(onFilter < [filter length] && !done)
    {
        char filterChar = [filter characterAtIndex:onFilter];
        char originalChar = onOriginal >= string.length ? '\0' : [string characterAtIndex:onOriginal];
        switch (filterChar) {
            case '#':
                if(originalChar=='\0')
                {
                    // We have no more input numbers for the filter.  We're done.
                    done = YES;
                    break;
                }
                if(isdigit(originalChar))
                {
                    outputString[onOutput] = originalChar;
                    onOriginal++;
                    onFilter++;
                    onOutput++;
                }
                else
                {
                    onOriginal++;
                }
                break;
            default:
                // Any other character will automatically be inserted for the user as they type (spaces, - etc..) or deleted as they delete if there are more numbers to come.
                outputString[onOutput] = filterChar;
                onOutput++;
                onFilter++;
                if(originalChar == filterChar)
                    onOriginal++;
                break;
        }
    }
    outputString[onOutput] = '\0'; // Cap the output string
    return [NSString stringWithUTF8String:outputString];
}

Now so that they can delete through filler, I modified my should change characters in range.

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {

    NSString *filter = @"(###) ### - ####";

    if(!filter) return YES; // No filter provided, allow anything

    NSString *changedString = [textField.text stringByReplacingCharactersInRange:range withString:string];

    if(range.length == 1 && // Only do for single deletes
       string.length < range.length &&
       [[textField.text substringWithRange:range] rangeOfCharacterFromSet:[NSCharacterSet characterSetWithCharactersInString:@"0123456789"]].location == NSNotFound)
    {
        // Something was deleted.  Delete past the previous number
        NSInteger location = changedString.length-1;
        if(location > 0)
        {
            for(; location > 0; location--)
            {
                if(isdigit([changedString characterAtIndex:location]))
                {
                    break;
                }
            }
            changedString = [changedString substringToIndex:location];
        }
    }

    textField.text = filteredPhoneStringFromStringWithFilter(changedString, filter);

    return NO;
}

This provides a really clean way to force users to enter numbers in a particular format.

Answer 4

Implement your logic inside textField:shouldChangeCharactersInRange:replacementString: which is a delegate method.