Working with Document Nodes and Styles - HTML, CSS, and Dynamic HTML - page 1004

To set the display status of that heading, you then can call the isHidden() function as
follows:

if (isHidden(TOCentry)) displayStatus = “none”
else displayStatus = “”;
Finally, you can apply the value of the displayStatus variable to the heading and subse-
quent element nodes using the command

n.style.display = displayStatus;
You'll add these commands to the expandCollapseDoc() function now.

To complete the expandCollapseDoc() function:

◗ 1. Scroll up to the expandCollapseDoc() function and then insert the following com-

mands within the first if condition:

var TOCentry = document.getElementById(“TOC” + n.id);
if (isHidden(TOCentry)) displayStatus = “none”
else displayStatus = “”;

◗ 2. Add the following command to the second if condition, as shown in Figure 14-55:

n.style.display = displayStatus;

Figure 14-55 completing the expandcollapsedoc() function

◗

3. Scroll up to the expandCollapse() function, and then add the following statements
to the end of the function (see Figure 14-56):

/* Expand and collapse the source document to match
the table of contents */
expandCollapseDoc();

Figure 14-56 completing the expandcollapse() function