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Eridana/UITextField phone string format

Created February 27, 2015 08:34
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  1. Eridana created this gist Feb 27, 2015.
    79 changes: 79 additions & 0 deletions UITextField phone string format
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,79 @@
    _textField.delegate = self (UITextFieldDelegate)

    - (NSMutableString *)filteredPhoneStringFromString:(NSString *)string withFilter:(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] copy];
    }


    - (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 = [self filteredPhoneStringFromString:changedString withFilter:filter];

    return NO;
    }