Check/Validate Date Format in JavaScript

Check/Validate Date Format in JavaScript

function checkDateFormate() {

            var date1 = $('#<%= date1.ClientID %>').val();

            var date2 = $('#<%= date2.ClientID %>').val();

            var date3 = $('#<%= date3.ClientID %>').val();

            var date4 = $('#<%= date4.ClientID %>').val();

          var arrayDates = ["date1", date1, "date2", date2, "date3", date3, "date4", date4];

            var var_return = false;

            var validformat = /^\d{2}\/\d{2}\/\d{4}$/

            var errorMsg1 = "";

            var errorMsg2 = "";

            var errorMsg3 = "";

            var dateVal = "";

            for (var i = 1; i < arrayDates.length; i = i + 2) {

                dateVal = arrayDates[i]; 

                if (dateVal != "") {

                    if (dateVal.length > 0) {

                        if (!validformat.test(dateVal)) {

         //alert("Invalid Date Format. Please correct and save/submit again (mm/dd/yyyy).");

                            errorMsg1 += '\n\u2022  ' + arrayDates[i - 1];

                            alert(errorMsg1);

                        }

                        else {

                            var monthfield = dateVal.split("/")[0]

                            var dayfield = dateVal.split("/")[1]

                            var yearfield = dateVal.split("/")[2]

                            var obj_Date = new Date(yearfield, monthfield - 1, dayfield)

                            obj_Date.setHours(0);

                            obj_Date.setMinutes(0);

                            obj_Date.setSeconds(0);

                            var todayDate = new Date();

                            todayDate.setHours(0);

                            todayDate.setMinutes(0);

                            todayDate.setSeconds(0);

                            if ((obj_Date.getMonth() + 1 != monthfield) || (obj_Date.getDate() != dayfield) || (obj_Date.getFullYear() != yearfield)) {

//alert("Invalid Day, Month, or Year range detected. Please correct and submit again (mm/dd/yyyy).");

                                errorMsg2 += '\n\u2022  ' + arrayDates[i - 1];

                                alert(arrayDates[i - 1]);

                            }

                            else {

                                var_return = true;

                                //if (Date.parse(obj_Date) < Date.parse(todayDate)) {

                       //    alert("Selected Date should be greater than or equal to Today.")

                                //}

                                //else {                               

                                //     var_return = true;

                                // }

                            }

                        }

                    }

                }

                //else {

                //    alert("Please enter Date.");

                //}

            }

            if (errorMsg1.length > 0 || errorMsg2.length > 0) {

                if (errorMsg1.length > 0 && errorMsg2.length > 0) {

                    alert('Invalid Date Format. Please correct and save/submit again (mm/dd/yyyy).' + errorMsg1 + '\n\n' + 'Invalid Day, Month, or Year range detected. Please correct and submit again (mm/dd/yyyy).' + errorMsg2);

                }

                else if (errorMsg1.length > 0) {

                    alert('Invalid Date Format. Please correct and save/submit again (mm/dd/yyyy).' + errorMsg1);

                } else if (errorMsg2.length > 0) {

                    alert('Invalid Day, Month, or Year range detected. Please correct and submit again (mm/dd/yyyy).' + errorMsg2);

                }

            }

            //if (errorMsg3.length > 0) {

            //    alert(errorMsg3);

            //}

            return var_return;

        }