根据出生日期填充下拉字段

Question

I was able to populate months, days and years. I was also able to determine the age, which in my end I am only allowing up to age 13.

Here is my code:

$('#reg-yr').change(function(){
    var year = $('#reg-yr').val();
    var month = $('#reg-mn').val();
    var date = $('#reg-dt').val();

    var firstdate=new Date(year,month,date);
    var today = new Date();
    var dayDiff = Math.ceil(today.getTime() - firstdate.getTime()) / (1000 * 60 * 60 * 24 * 365);
    var age = parseInt(dayDiff);
});

This code checks the age when year was change. What I am having problem right now, is how to populate the month drop-down field based on the age.

For example: The date today is June 13, 2014

My default date in my birthday drop-down is January 1, 1980

What I wanted is for example when I change the year to 2001, the month will be populated based on maximum age.

So the drop-down should be only consisting months of January down to May.

JSFIDDLE

Thank you for the help.

Answer 1

     $('#reg-yr').change(function(){
             var months =['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'];
        var year =  $('#reg-yr').val();
        var month = $('#reg-mn').val();
        var date = $('#reg-dt').val();
         var today = new Date();
         var i = 0;
        for(i=0;i <= 12;i++)
        {
            var firstdate=new Date(year,i,date);
             var dayDiff = Math.ceil(today.getTime() - firstdate.getTime()) / (1000 * 60 * 60 * 24 * 365);
             var age = parseInt(dayDiff);

            if(age < 13)
                break;
        }

$('#reg-mn').html('')
        for(j=0;j <(i-1);j++)
        {
            $('#reg-mn').append('<option value="'+ j +'">'+ months[j] +'</option>') ;
        }
    });

See solution on js fiddel

Updated on JSFIDDLE also

Answer 2

Try this...

$('#reg-yr').change(function(){
    var year = $('#reg-yr').val();
    var month = $('#reg-mn').val();
    var date = $('#reg-dt').val();

    var firstdate=new Date(year,month,date);
    var today = new Date();
    var dayDiff = Math.ceil(today.getTime() - firstdate.getTime()) / (1000 * 60 * 60 * 24 * 365);
    var age = parseInt(dayDiff);


    html = '<option value="">Select Month</option>';
    for(i=1;i<=age;i++) {
        html += '<option value="'+i+'">'+i+'</option>';
    }

    $('select').html(html);

    });