Rules are probably best described by using examples. This chapter contains numerous real world samples.

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Step 1 is named Expense Report, Step 2 is named Manager Approval and step 3 is named Accounting in the flow designer to match the sections in the parent form. The Manager role has been assigned to step 2 and the Accounting role has been assigned to step 3.

Here is an example of a rule that shows the Expense report details when the form loads, (the Manager Approval and Accounting sections are hidden) on step1, makes the Manager Approval section visible in the second step of the flow when performed by a manager and shows the Manager Approval and Accounting sections on step 3 when it is performed by an accounting department employee.

if (form.load) {
    var an = _data.getParameter("flow.activity.name");
    if (an === 'Manager Approval') {
        ManagerApproval.visible = true;
    }
    if (an === 'Accounting') {
        ManagerApproval.visible = true;
        Accounting.visible = true;
    }
}

Show/Hide Manager Approval on Step 2 and 3 of a flow

You have a flow and the first form has a Section for manager approval. The Section is hidden by default. Here is an example of a rule that makes the section visible in the second and third steps of the flow which are linked steps assigned to the manager and VP roles. 

if (form.load) {
  var an = _data.getParameter ("flow.activity.name");
  if (an === 'Manager' || an === 'VP'){
    ManagerApproval.visible = true;
  } else {
    ManagerApproval.visible = false;
  }
}

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You can build forms/flows In that meet Section 508 and WCAG 2.0 accessibility standards. Accessible forms/flows can assist users with visual and motor impairments. When the Accessible property is enabled for a form/flow, the error, "You can't leave this empty <control name>"  displays, if users move ahead from a required field without filling it. The status property for the empty control becomes invalid and sets the error message. Normally, the status property can be used in a business rule. For example, let's say a form has a text control named 't', and a message control named "m". If you write a rule to update the message field (control named m) with the STATUS of the required/invalid control (control named t), as shown below, it will not work because the "You can't leave this empty" message for a required control is not treated as it's status.

if(!t.valid)
  {
    m.value = t.status;
  }

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You may want to calculate a date in a workflow based on a five day work week. This is a common business scenario and may be helpful if you are using the   Escalations feature. It is not possible to select calendar or working days for the Days interval of the Escalation feature at this time but this enhancement is planned for a future release. As a work-around, you can calculate X number of working days from the current date, and set that date in a Date control on your form. Then while configuring escalations, use the ‘Complete By’ condition and select the Date control.

Here is the business function/rule that will add 3 working days to the current date to give you the escalation date. Copy/paste the entire rule including the function in the Rule Editor. Substitute the name of your date control for <your date control>:

 function calcWorkingDays(fromDate, days) {
    var count = 0;
    while (count < days) {
        fromDate.setDate(fromDate.getDate() + 1);
      if (fromDate.getDay() !== 0 && fromDate.getDay() !== 6) {  // Skip weekends
            count++;
      }
    }
    return fromDate;
}
 
if (form.load && <your date control>.value.length === 0){
  var numWorkingDays = 3; 
  var today = frevvo.currentDate().split('-');
  var escDate = calcWorkingDays(new Date(today[0], today[1]-1, today[2]), numWorkingDays);
  var m = escDate.getMonth() + 1;
  var d = escDate.getDate();
  var y = escDate.getFullYear();
  <your date control>.value = m + '-' + d + '-' + y;
}

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var date = datefield.value.split('-');
var dateStr = date[2] + '/' + date[1] + '/' + date[0] ;
Msg.value = "I selected the date: " + dateStr;

Checking a Date for Extra Digits

This rule uses the valid property to verify that the entered date does not contain extra digits. For example, if a user enters a date with a 6 digit year (1/2/201717) into a control named StartDate, the customized error message displays.

if (StartDate.value.length > 10) {
  StartDate.valid = false;
  StartDate.status = 'Invalid. Please check that the date is entered in the mm-dd-yyyy format'; 
} else {
  StartDate.valid = true;
} 

Times

The date control can be set to either just a date, just a time, or a combined date/time. Here are several examples of initializing a time control named Tm;

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Imagine an airline reservation form where the number of traveler information sections displayed is based on the number of airline tickets purchased. There is a field in the form for the number of tickets named count, and a repeat named TravelRepeat with a section including controls to collect information about each traveler.  You can leave the default values for the Min/Max properties of the Section in the Forms designer or set them to any values provided the min value < max value and the max value  > min value.

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This is an example of a business rule that displays the number of sections based on the number of purchased airline tickets. Min/Max for the section are set to 1 and 20 in the forms designer. 

var i;
if (TravelRepeat.itemAdded) {
    i = TravelRepeat.itemIndex;
    TravelNo[i].value = 1 + i;
} else {
    if (count.value > TravelNo.value.length){
        TravelRepeat.maxOccurs = count.value;
        TravelRepeat.minOccurs = count.value;
    } else {
        TravelRepeat.minOccurs = count.value;
        TravelRepeat.maxOccurs = count.value;
    }
    for (i=0; i<TravelNo.value.length;i++) {
        TravelNo[i].value = 1 + i;
    }
} 

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1. The first part of your rule should retrieve the results set (this part of the rule is not shown here). In this example, the user enters a number in the Number of Travelers field in the form.
2. The itemAdded statement is needed to determine if you are adding more sections. The first time the rule runs, this statement will evaluate as false and run the else statement
3. Evaluate if the number of sections needed is greater than the number or existing sections. If true, set the maxoccurs first because the table needs to increase.
4. if If the number of sections needed is less than the number of existing sections then set the minoccurs first.
5. The rule will loop through the existing sections and set the values in the TravelNo field. If there are still additional sections to be added after the rule has looped through the existing sections, the itemAdded lines will run.
6. This rule sets the Min/Max properties to the same values so the  plus and  minus icons are not visible. This  prevents users from adding or removing repeating items.

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Let's take a look at a simple example. Users are instructed to enter a capital Y in a table if they are planning on calling a customer. The user enters the "Y" then tabs to the company name column. The minus icon for that row will disappear.  

In this example, the name of the table control is CustomerTable and column 0 in the table is named ContactCustomer.

Here is the rule:

for (var i=0; i<ContactCustomer.value.length; i++) {
    if (ContactCustomer[i].value === "Y") {
        CustomerTableItem[i].deletable = false;
    } else {
        CustomerTableItem[i].deletable = true;
    }
}

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For example, lets say you have a form that collects how many travelers are planning to travel. When the user enters a number of travelers, the table will populate with the same number of rows as travelers and populate the column for Traveler ID with an ID number. The form will adjust if the number of travelers is changed. 

You can leave the default values for the Min/Max properties of the Table in the Forms designer or set them to any values provided the min value < max value and the max value  > min value.

In this scenario, it is best practice to write 1 rule to handle the table, logic to loop through the rows of the table and itemadded for when another row is added to the table. 

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1. The first part of your rule should retrieve the results set or as in this example, the user can enter a number in the Number of Travelers field in the form.
2. The itemAdded statement is needed to determine if you are adding more rows to the table.The first time the table populates this statement will evaluate as false and run the else statement
3. Evaluate if the number of rows needed is greater than the number or existing rows. If true, the table needs to set the maxoccurs first because the table needs to increase.
4. if If the number of rows needed is less than the number of existing rows (the table needs to shrink) then the table needs to set the minoccurs first.
5. The rule will loop through the existing rows and set the values in the appropriate columns. If there are still additional rows to be added to the table, after the rule has looped through the existing rows, the itemAdded lines will run.
    

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/*member num */
var x;
 
if (form.unload) 
{ 
    eval('x=' + http.get('http://(your webhost)/json/getNextOrdernum'));  
    OrderNum.value = x.num;
}

Geo Location

Rules can be used to save a snapshot of location information of any form. For example, an insurance company may want to capture the GPS location of their representatives filling out a form used for audit purposes. The designer can use the  Geo Location feature in conjunction with rules like the ones shown in the examples below to accomplish this. When the form loads in the browser, the user will be prompted by to allow/disallow the use of location services. If permission is granted, the position will be calculated and server will be updated via an Ajax which causes the rule to fire. If the user denies permission or there is a timeout, the server will get an Ajax with an error.

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A rule can dynamically display an image uploaded to your form via the upload control. In this example the upload control is named 'u'. The form also must contain a message control as a place holder for displaying the uploaded image. The rule dynamically creates a URL to the uploaded image in the temporary attachment repository. The upload control's value 'u.value' is a GUID that uniquely identifies the attachment. The uploaded image will be included in the submission PDF.

if (u.value.length > 0) {
  var baseUrl = "/frevvo/web/tn/" +
      _data.getParameter('tn.id') +
      "/user/"+_data.getParameter('user.id') +
      "/app/"+_data.getParameter('app.id') +
      "/form/"+_data.getParameter('form.id');
 
  im.value = '<img src="' +
         baseUrl + '/attachment/' + u.value+'/does_not_matter"/>';
}

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