html input with javascript . adding

When the date of birth is entered in my input, I want a full stop after 2 characters are entered automatically. I know it’s done with toLocaleLowerCase

Sample:
01011980

Output:
01.01.1980

>Solution :

If the sample is always fixed length which I guess it is, you can do it like this:

var sample = '01011980';

function processString(inputString){
    return inputString.substr(0,2)+'.'+inputString.substr(2,2)+'.'+inputString.substr(4,4);
    
}

output = processString(sample);

alert(output);