Question

I know there are many NSDateFormatter questions on here, so if I duplicate, I’m sorry. I just couldn’t find anything that was quite what Im asking.

From all the questions here on SO, I have come to the conclusion that -[NSDateFormatter dateFromString:] will always return NULL if your formatter object doesn’t have the correct date format. How do you get a date from a string if you don’t know the format? I’m trying to get a date from a UITextField.

NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setLocale:[NSLocale currentLocale]];
[formatter setLenient:YES];
NSDate *tempDate = [formatter dateFromString:self.birthdayTxtfld.text];
self.currentCustomer.birthday = ([self.birthdayTxtfld.text isEqualToString:@""]) ? NULL : tempDate;
[formatter release];

tempDate is always NULL.

Answer 1

I think your taking the wrong approach. I would on the other hand restrict and format the UITextField so the user has to enter the date in a specific format. Or just use a date picker. There are just way too may different inputs the user could give you.

Or you can read through this: NSDate

Another option is to create a list of accepted date formats:
#define DATEFORMATS @[@"MM/dd/yyyy", @"MM/dd/yy",...
Then Have a method that you pass the date string to and check if you can format it:

+ (NSDateFormatter*)getDateFormat:(NSString*)dateString {

    NSArray *dateFormats = DATEFORMATS;
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    NSDate *date = nil;
    for (NSString *dateFormat in dateFormats) {
        [formatter setDateFormat:dateFormat];
        date = [formatter dateFromString:dateString];
        if (date) {
            return formatter;
        }
    }
    return nil;
}

If you get nil its not a date or its in a format you don’t support. Otherwise you will have the correct format you need. You can switch this around to return the date instead of the format. I have it this way because I needed the format not the date for a project.