Sure!
Rich text fields consist of HTML as content. These HTML tags are child nodes
of the XML node representing the rich text box field. You can get to these
child nodes by using code. If you add <div> elements as child nodes of the
rich text box field, you will get lines. To make these lines visible, just
give the bottom border of each <div> element a color.
Try this: Make sure the programming language of your form is set to JScript
by going to Tools > Options > Design tab > Default programming language. Add
a rich text box to your form and make sure its name is "field1". Go to Tools
Programming > On Load Event to add an OnLoad event handler for your form.
Copy and paste the following code in the OnLoad event.
var rtfNode = XDocument.DOM.selectSingleNode("//my:field1");
var childNode = XDocument.CreateDOM();
childNode.loadXML("<div xmlns=\"
http://www.w3.org/1999/xhtml\"
style=\"border-bottom:#CCC 1px solid; width:100%; padding:5px;\"></div>");
rtfNode.appendChild(childNode.documentElement);
var childNode2 = XDocument.CreateDOM();
childNode2.loadXML("<div xmlns=\"
http://www.w3.org/1999/xhtml\"
style=\"border-bottom:#CCC 1px solid; width:100%; padding:5px;\"></div>");
rtfNode.appendChild(childNode2.documentElement);
This will add 2 lines in the rich text box when the form loads. Preview your
form. This is the closest you will get to having lines in a rich text box.