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

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Show/Hide Manager Approval

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 step of the flow which is a linked activity assigned to the manager role. 

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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if (ExpenseRepeat.itemRemoved) {var x;} 

Formatting money values to display in a Message Control

Let's say you have calculated a sum in a Number control in your form and you want to display it in a Message control and format it as a money value with commas and decimal places.  You will need a Number control named Num and a message control named Message in your form. This rule will display the number entered in the number control with commas. If the user enters 5600.44 in the number field then the result in the message control would look like this:"5,600.44".

var x, x1, x2;
if (Num.value > 0) {
    var nStr = Num.value.toFixed(2);
    nStr += '';
    x = nStr.split('.');
    x1 = x[0];
    x2 = x.length > 1 ? '.' + x[1] : '';
    var rgx = /(\d+)(\d{3})/;
    while (rgx.test(x1)) {
 x1 = x1.replace(rgx, '$1' + ',' + '$2');
    }
    Message.value = x1 + x2;
}

Textarea Max Length

In html there is no way to set a maxLength on a textarea control. This is why the textarea control does not have a maxlength property like the text control does. It is possible to do this via a business rule. This example form has a textarea control named 'Desc' where the user can enter up to a 500 character description. On this control we also set the ErrorMsg property to the string 'You must limit your description to 500 characters'. This message is automatically displayed when the description control is set to invalid by the following business rule.

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