how to get difference between two date/time type of fields and populate it in a field which is of duration type

[akshay parekar1]

Hello Guys,please help me to achieve this,

For my  custom table, i have created two date/time type of fields which are Start Date and End Date.

I have created  third field also named as Duration  which is of duration type

Now, whenever value of End Date field changes on the form, my duration field should populate the difference between Start Date and End Date in duration form( days and difference in time)

To achieve this i have written a script include and called it from onchange type of client script(Field name= End Date), 

still my Duration field is not getting populated as i desired

please see my script and help me out, Thanks in advance!!

Script Include:

var DurationCalculation = Class.create();
DurationCalculation.prototype = Object.extendsObject(AbstractAjaxProcessor, {
getDuration: function() {
var dateTimediff;
    var date1= new GlideDateTime();
    var date2= new GlideDateTime();
    
    var fromdate= this.getParameter('sysparm_from_date');
    var todate= this.getParameter('sysparm_to_date');
    
    date1.setValue(fromdate);
    date2.setValue(todate);
    
    dateTimediff=GlideDateTime.substract(date1,date2);
    return dateTimediff.getDisplayvalue();
},
    type: 'DurationCalculation'
});

Client script:(Type- onChange and field name-End Date)

function onChange(control, oldValue, newValue, isLoading, isTemplate) {
    if (isLoading || newValue === '') {
        return;
    }

    var fromdate = g_form.getValue('u_start_date');
    var todate = g_form.getValue('u_end_date');
    
    var ga= new GlideAjax('DurationCalculation');
    ga.addParam('sysparm_name','getDuration');
    ga.addParam('sysparm_from_date',fromdate);
    ga.addParam('sysparm_to_date',todate);
    ga.getXML(CBF);
    
    function CBF(response){
        var answer= response.responseXML.documentElement.getAttribute("answer");
        g_form.setValue('u_duration',answer);
        
    }

}

[Pavankumar_1]

Hi,

If you use business rule to get this requirement then use below code.

(function executeRule(current, previous /*null when async*/ ) {

    var gdtStart = new GlideDateTime(current.getValue('work_start'));  //give your start date column name
    var gdtEnd = new GlideDateTime(current.getValue('work_end')); //give your end date column name
    var duration = new GlideDateTime.subtract(gdtStart, gdtEnd); //difference between gdtStart and gdtEnd
    current.u_duration = duration.getDurationValue();  //update to your duration field

})(current, previous);

Thanks,

Pavankumar