Manual date entry validation for jQuery UI Datepicker maxDate option

Well, the above answer is correct, but it does not validate the form, the user still will be able to submit the form,

I have done some researches, but could not find ny, finally I wrote this function which works fine and validate the form, and does not let submit the form until the correct date is entered, Hope it helps!

The only thing you need to do is add this code, and then this will be applied to all the fields with 'datePicker' class.

 $(".datePicker").datepicker({
            dateFormat: 'd/mm/yy',
            changeMonth: true,
            changeYear: true,
            firstDay: 1,
            minDate: Date.parse("1900-01-01"),
            maxDate: Date.parse("2100-01-01"),
            yearRange: "c-90:c+150"
        });

        // validation in case user types the date out of valid range from keyboard : To fix the bug with out of range date time while saving in sql 
        $(function () {
            $.validator.addMethod(
                "date",
                function (value, element) {

                    var minDate = Date.parse("1900-01-01");
                    var maxDate = Date.parse("2100-01-01");
                    var valueEntered = Date.parse(value);

                    if (valueEntered < minDate || valueEntered > maxDate) {
                        return false;
                    }
                    return !/Invalid|NaN/.test(new Date(minDate));
                },
                "Please enter a valid date!"
            );
        });

I am not sure if datepicker fires an event if the control's value is changed by typing in directly. You can bind a function to the .change() event:

$(".datepicker").attr("placeholder", "mm-dd-yyyy").datepicker({
    dateFormat: "mm-dd-yy",                 // since you have defined a mask
    maxDate: "+1",
    showOn: "button",
    showOtherMonths: true

}).on("change", function(e) {
    var curDate = $(this).datepicker("getDate");
    var maxDate = new Date();
    maxDate.setDate(maxDate.getDate() + 1); // add one day
    maxDate.setHours(0, 0, 0, 0);           // clear time portion for correct results
    if (curDate > maxDate) {
        alert("Invalid date");
        $(this).datepicker("setDate", maxDate);
    }
});

Demo here

One option is to remove the ability to manually enter a date by making the input fields readonly. This will restrict the user from manually entering anything crazy, and forces the use of the datepicker.

I had exactly the same requirement and here is the solution that worked for me like a charm:

  $(".datepicker").attr("placeholder", "mm-dd-yyyy").change(function(){
    $(this).datepicker('setDate', $(this).datepicker('getDate'));
  }).datepicker({
      showOn: "button",
      maxDate: "+1",
      showOtherMonths: true
  });

Modified fiddle here referenced from Salman A's answer