Question

I have written a JS that should check that start date is less than end date. If not, alert should be thrown

The JS is written as;

function DateValidation(startDate, EndDate) {
                debugger;
                var stdate = startDate;
                var enddate = EndDate;
                if (stdate!= '' && enddate!='') {
                if (stdate > enddate) {
                    alert('Start date cannot be greater than end date');
                    return false;
                }
                else {
                    return true;
                }
               }
            }

This JS gets fired when i am clicking a button as “Show Report”.

Problems that i am facing

1. JS doesn’t validate the date correctly. What am i missing? i am passing date from the textbox

2. The JS doesn’t fired up when clicking button for the first time. it fires when clicking the button second time

Plus, i have registered the JS as below;

btnShowReport.Attributes.Add("onclick", "return DateValidation('" + txtStartDate.Text + "', '" + txtEndDate.Text + "');");

Is the above code correct? What is the correct place to register the JS?

Please guide.. thanks!

Answer 1

You need to parse the string values to dates

if (startDate!= '' && EndDate!='') {  
    var stdate = Date.parse(startDate);   
    var enddate = Date.parse(EndDate);  
    if (stdate > enddate) {   
        alert('Start date cannot be greater than end date');   
        return false;   
    }   
    else
    {   
        return true;   
    }   
} 

Without further code it’s hard to tell why your button only fires the event on the second click. Is your button disabled to start with?