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Validate Date field on the form after fetching from the script

Sampathr382
Tera Contributor

3 hours ago

Hi Community people,

I have a field called "Request is existing or new?" on the catalog form and it has 2 values i.e., New and Existing.
1.If a user selects 'New' option then all the fields like planned start date , planned end date will appear with empty values. So if a user changes anything on the planned start end date, I wrote a validation script(onchange script) that it will not allow to select a date which is less than 20 days from today's date and it will clears the value if the date is less than 20 days.
2. if a user selects 'Existing ' option then all the fields like planned start date , planned end date are populated with exiting values of a request. But the planned start date is also getting cleared if the date is less than 20 days. I don't want that, whatever the value is there while fetching it should be there in planned start date and if user changes anything on planned start date then on change should be triggered?

Any suggestions or workaround? 

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1 REPLY 1

sachinvic
Giga Guru

6m ago - last edited 2m ago

Hi Sampath,
The issue happens because the onChange script naturally fires when the "Existing" data is initially fetched and loaded onto the form, triggering your validation and clearing the field.

To fix this, you must use isLoading to block execution during the initial load, and use GlideAjax to handle the 20-day date calculation securely on the server side (client-side date math using new Date() is unreliable due to timezone variations).
 
Follow these two steps to resolve the issue:

Step 01: Create a Client-Callable Script Include

Create a new Script Include, check the Client callable checkbox, and paste this code:

var DateValidationUtils = Class.create();
DateValidationUtils.prototype = Object.extendsObject(AbstractScriptProcessor, {

    validateDateRange: function() {
        var selectedDateStr = this.getParameter('sysparm_selected_date');
        
        var now = new GlideDateTime();
        var selectedDate = new GlideDateTime(selectedDateStr);
        
        // Add 20 days to current system time
        now.addDaysLocalTime(20);
        
        // Return invalid if the date is less than 20 days from today
        if (selectedDate.getNumericValue() < now.getNumericValue()) {
            return 'invalid';
        }
        return 'valid';
    },

    type: 'DateValidationUtils'
});

 

Step 02: Update your onChange Client Script

Update your field's onChange Client Script with the following structure. The isLoading and newValue == oldValue checks will perfectly protect your fetched data:
function onChange(control, oldValue, newValue, isLoading, isTemplate) {
    // 1. Prevents execution during initial fetch/load or if field is cleared
    if (isLoading || newValue === '' || newValue == oldValue) {
        return;
    }

    // 2. Call the server script to validate the date
    var ga = new GlideAjax('DateValidationUtils');
    ga.addParam('sysparm_name', 'validateDateRange');
    ga.addParam('sysparm_selected_date', newValue);
    ga.getXMLAnswer(function(response) {
        if (response === 'invalid') {
            g_form.clearValue(control.name); // Clears the field automatically
            alert('The selected date must be at least 20 days from today.');
        }
    });
}​

 

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Regards,
Sachinvic
✨ArchX Certified | ✨16x ServiceNow AI MVP

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