Field script use cases

reference australia Updated Sep 10, 2026 6 min read r_UsefulFieldScripts.md
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Common use cases for field customization scripts.

Warning: The customization described here was developed for use in specific instances, and is not supported by Now Support. This method is provided as-is and should be tested thoroughly before implementation. Post all questions and comments regarding this customization to our community forum.

For more information, see Server API reference.

Automatically populate a field

The following example shows how to use a client script to auto-fill a Short Description based on the selected Subcategory.

In this case, if the table has a record with Subcategory = Password and Short Description = Password Reset. When the user selects the Subcategory of Password on the Incident form, a client script looks up the matching record and sets Short Description equal to Password Reset.

Client script settings:

  • Type = onChange
  • Table name = incident
  • Field name = Subcategory
JavaScript
function onChange(control, oldValue, newValue, isLoading){    if(isLoading){return;}    var newrec = gel('sys_row');    //Check if new record    if (newrec.value == -1) {        var lookup = new GlideRecord('u_short_desc_lookup');        lookup.addQuery('u_subcategory', g_form.getValue('subcategory'));        lookup.query();        var temp; //temp var - reusable        if(lookup.next()){            temp = lookup.u_short_description;            if(null != temp) {                //Set the form value from lookup if there is a lookup value                g_form.setValue('short_description', temp);            } else {                g_form.setValue('short_description',"");                }          } else {              //If a lookup record does not exist based on lookup.addQuery              //Then set to UNDEFINED or NULL depending on type              g_form.setValue('short_description',"");              }     }}

Disable HTML tags in descriptions

This code disables HTML tags in Description and Short Description fields by substituting the tags with non-executing versions.

JavaScript
doit(); function doit(){  var desc = current.description.toString(); var shdesc = current.short_description.toString(); if(desc.indexOf('script>')>-1|| shdesc.indexOf('script>')>-1){   desc = desc.replace(/<script>/g,"(script)");   current.description = desc.replace(/<\/script>/g,"(\/script)");   shdesc = shdesc.replace(/<script>/g,"(script)");   current.short_description = shdesc.replace(/<\/script>/g,"(\/script)");}}

Eliminate leading and trailing spaces in fields

This example of the script trims trailing and leading spaces in the FirstName and LastName fields of the sys_user.

JavaScript
doit(); function doit(){   var now_GR =new GlideRecord('sys_user');  gr.query();  while(gr.next()){    if((gr.first_name.toString().length!= gr.first_name.toString().trim().length)||(gr.last_name.toString().length!= gr.last_name.toString().trim().length)){     gr.first_name= gr.first_name.toString().trim();     gr.last_name= gr.last_name.toString().trim();     gr.autoSysFields(false);     gr.update();}}}

Make a field label flash

The following client script example is for the number field on incident. The label flashes for two seconds.

JavaScript
g_form.flash("incident.number","#FFFACD",0);

The arguments for the flash method are as follows:

  • tablename.fieldname
  • RGB color or acceptable CSS color like "blue" or "tomato"
  • Integer that determines how long the label flashes:
    • 2 for a 1-second flash
    • 0 for a 2-second flash
    • -2 for a 3-second flash
    • -4 for a 4-second flash

Note: Do not specify this argument if you want the field label colored the specified color.

Make a field label bold

This client script makes the label of a particular field bold. In this case, the field is the Short Description on the Incident Table.

JavaScript
function onLoad(){  var l = g_form.getLabel('incident.short_description');  l.style.fontWeight = 'bold';}

Make fields read-only

This onLoad client script makes the following fields on the Incident [incident] table read-only:

  • Incident state
  • Impact
  • Urgency
  • Priority
  • Configuration item
  • Assigned to

The script also removes the magnifying glass for the read-only Reference Fields (Configuration item and Assigned to).

JavaScript
function onLoad(){var incidentState = g_form.getValue('incident_state');if( incidentState == '6'|| incidentState == '7'){   g_form.setReadonly('incident_state',true);   g_form.setReadonly('impact',true);   g_form.setReadonly('urgency',true);   g_form.setReadonly('priority',true);   g_form.setReadonly('cmdb_ci',true);   g_form.setReadonly('assigned_to',true);}}

Set current date/time in field

You can set date and time values in client scripts and script includes.

  • Client script

    You can use the following two lines to set the current date and time in a date/time field. This approach bypasses the problem of getting the value into the proper format and proper time zone.

    JavaScript
    var ajax = new GlideAjax('MyDateTimeAjax');  ajax.addParam('sysparm_name','nowDateTime');  ajax.getXML(function(){    g_form.setValue('put your field name here', ajax.getAnswer());});

    For more information on running server-side scripts with the client, refer to GlideAjax.

  • System script include

    JavaScript
    // Be sure the Glide AJAX enabled option is checked var MyDateTimeAjax = Class.create();MyDateTimeAjax.prototype = Object.extendsObject(AbstractAjaxProcessor,{  nowDateTime:function(){    return gs.nowDateTime();}});

Toggle the timer field by field name

The following client script toggles the timer field based on a particular field name.

JavaScript
function toggleTimerByFieldName(fieldName){ //Step 1: Find the timer object //timeObjectName: the timer objects name as it would normally be referenced //timeObjectHidden: the hidden input node in the field td //timeObjectParent: the parent td node containing the field and it's constituent nodes //timeObjectFields: anchor tag with onclick to stop timer  var timeObjectName = fieldName; var timeObjectHidden = gel(timeObjectName);  //Step 2: simulate click stop button var timeObjectParent; var timeObjectFields;  //verify that we got the correct object if(timeObjectHidden.type=="hidden"){     //Get Parent td node    timeObjectParent = timeObjectHidden.parentNode;     //Get input fields    timeObjectFields = timeObjectParent.getElementsByTagName("input");     //simulate click of stop button    var timerTestString ="paused";    var timerImg;     //loop through input objects looking for the pause timer object    for(var elIt=0; elIt < timeObjectFields.length; elIt++){      if(timeObjectFields[elIt].id.match(timerTestString)){        if(timeObjectFields[elIt].value=="false"){          timeObjectFields[elIt].value="true";          timerImg = timeObjectParent.getElementsByTagName("img")[0];          timerImg.src="images/timer_start.gifx";}      elseif(timeObjectFields[elIt].value=="true"){          timeObjectFields[elIt].value="false";          timerImg = timeObjectParent.getElementsByTagName("img")[0];          timerImg.src="images/timer_stop.gifx";}}}}}

Modify GlideDateTime field values

The following server-side script example shows how to modify values using the GlideDateTime API. The same concept also applies to the GlideDate object.

Note: The following script is only intended for global applications.

JavaScript
//You first need a GlideDateTime object//this can be from instantiating a new object "var gdt = new GlideDateTime()"//or getting the object from a GlideDateTime field//getting the field value (for example: var gdt = current.start_date) only returns the string value, not the object//to get the object use var gdt = current.start_date.getGlideObject(); (GlideElement)//now gdt is a GlideDateTime objectvar gdt = current.start_date.getGlideObject(); //All methods can use negative values to subtract intervals //add 1 hour (60 mins * 60 secs)gdt.addSeconds(3600); //add 1 daygdt.addDaysLocalTime(1); //subtract 1 daygdt.addDaysLocalTime(-1); //add 3 weeksgdt.addWeeksLocalTime(3); //subtract 6 monthsgdt.addMonthsLocalTime(-6); //add 1 year, representing the date and time using the UTC timezone instead of the local user's timezone.gdt.addYearsUTC(1); //set the value of the GlideDateTime object to the current session timezone/formatGlideSession.get().setTimeZoneName('US/Eastern');gdt.setDisplayValue('2018-2-28 00:00:00');gs.info('In ' + GlideSession.get().getTimeZoneName() + ": " + gdt.getDisplayValue());

See also:

Parent Topic:Example scripts

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