objective c - Inserting a comma for integers when there are three digits added everytime to the textfield in iOS -

i need add comma separating numbers 3 digits without white spaces , if total digits under three, no comma added.

for example:

2984 => 2,984 297312984 => 297,312,984 298 => 298 

how solve this?

tried this:

if([textfield.text length] > 3) {  nsmutablestring *stringtext = [nsmutablestring stringwithstring:textfield.text];  [stringtext insertstring:@"," atindex:0]; } 

abt after starting, started think if there better solution? because there lot of if-else statements.

welcome suggestion.

this i've come with: set delegate of text field, , implement following method accordingly:

- (bool)textfield:(uitextfield *)textfield shouldchangecharactersinrange:(nsrange)range replacementstring:(nsstring *)string {     if (textfield.text.length % 4 == 3) {         if (string.length != 0) {             textfield.text = [nsstring stringwithformat:@"%@,%@", textfield.text, string];             return no;         }     }      return yes; }