Compare Phone Numbers with different format - ios

Question

Phone nubmber can have different Formats , like 0XXXXXXXXXX or +91XXXXXXXXXX or XXXXXXXXXX.
In all cases , phone number is similar.
How can i compare ?

Answer 1

Please do this for love of god: Handling all formats of phone numbers is as tricky and hairy as handling different data formats. It's always a sane option to use some existing "mature" library. Use PhoneNumberKit, its one of the mature and popular libraries out there.
But if you want to live on the edge, you can try something like this -
Reverse the string & compare only the first 10 chars.
Regular Expressions would be a better solution. Have as many regular expressions as there are formats & you are good to go.
Please open source this library for others to benefit :)
General reading on handling phone numbers

Answer 2

You could start comparing right to left using a custom character by character match code. It also works because the last few digits on phones vary more than the first few, so your code will fail fast in a unequal comparison which is what you want anyways. Keep a count of how many matches you have and if it passes a certain threshold say 10, then call the number equal. Without know more specifics this would be made to work reasonably well.

Answer 3

As Mentioned by srikar to reverse the string and compare 10 characters.Create the method and call it for all the three strings and after that compare them.
NSMutableString *reversedString = [NSMutableString string];
NSInteger charIndex = [myString length];
NSInteger count;
count=10;
while(count >= 0) {
count--;
charIndex--;
NSRange subStrRange = NSMakeRange(charIndex, 1);
[reversedString appendString:[myString substringWithRange:subStrRange]];
}