JavaScript document map

JavaScript code to generate a document map/table of contents from the document structure.

NB – Sorry I need to update this to get the examples working in WordPress

This page generates the following document map:

[jscript]

[brushjs]

function get_my_navigation(use_body, html_text, do_bookmarks, heading_level, show_level) {    

    

	//var all_elements = document.getElementsByTagName("*");

    var all_elements;



    if (use_body == 1)

        all_elements = document.getElementsByTagName("*");

    else if (html_text!=""){

        html_div = document.createElement("div");

        html_div.innerHTML = html_text;

        all_elements = html_div.getElementsByTagName("*");

    }

    if ((heading_level==null) || (heading_level==""))

        heading_level=3;

    if (show_level==null)

		show_level=0;

    var hopen="&lt;h"+heading_level+"&gt;";

    var hclose="&lt;/h"+heading_level+"&gt;";

    

    structure = "";

    first_level = 0;

    level_no = 0;

    this_level = 0;

    last_level = 0;

    current_level = 0;



    for (i = 0; i &lt; all_elements.length; i++) {

        h_message = "";

        element_text = "";

        a = all_elements[i];

        if (document.all) {

            element_text = a.innerText;

        } else {

            element_text = a.textContent;

        }

        node_name = all_elements[i].nodeName;

        if (node_name == "H1" || node_name == "H2" || node_name == "H3" || node_name == "H4" || node_name == "H5" || node_name == "H6") {

            level_no++;            

                

            this_level = parseInt(all_elements[i].nodeName.substring(1, 2));

            if (level_no == 1)

                first_level = this_level;

            if (show_level==1)

				element_text+=" ("+this_level+")";

                            

            // if we are bookmarking the contents  

            if (do_bookmarks==1)

                element_text = "&lt;a href='#generated_link_" + i + "'&gt;" + element_text + "&lt;/a&gt;";



            if (this_level == last_level) {



                if (first_level == this_level)

                    structure += hopen + element_text + hclose;

                else

                    structure += "&lt;li&gt;" + element_text + "&lt;/li&gt;";

            }

            else if (this_level &gt; last_level) {

                current_level++;

                difference = this_level - last_level;





                if (difference &gt; 1) {

                    h_message = " (bad heading structure)&lt;/li&gt;";

                }



                if (first_level == this_level)

                    structure += hopen + element_text + hclose;

                else

                    structure += "&lt;ul&gt;&lt;li&gt;" + element_text + h_message + "&lt;/li&gt;";

            }

            else if (this_level &lt; last_level) {            

                difference = last_level - this_level;

                for (z = 0; z &lt; difference; z++) {

                    current_level--;

                    structure += "&lt;/ul&gt;";

                }

                structure += "&lt;/ul&gt;";

                if (current_level &lt; 0)

                    structure += "&lt;li&gt;" + element_text + "&lt;/li&gt;  (bad heading structure)";

                else {

                    if (first_level == this_level)

                        structure += hopen + element_text + hclose;

                    else

                        structure += "&lt;ul&gt;&lt;li&gt;" + element_text + "&lt;/li&gt;";

                }

            }

            

            if (do_bookmarks == 1) {

                var lnk = document.createElement("a");

                lnk.name = "generated_link_" + i;

                lnk.id = "generated_link_" + i;

                all_elements[i].appendChild(lnk);

            }

            last_level = this_level;

        }

    }

    for (z = 0; z &lt; current_level; z++) {

        structure += "&lt;/ul&gt;";

    }

    return structure;   

}

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[brushjs]

function get_my_navigation(use_body, html_text, do_bookmarks, heading_level, show_level) {

//var all_elements = document.getElementsByTagName("*");

var all_elements;

if (use_body == 1)

all_elements = document.getElementsByTagName("*");

else if (html_text!=""){

html_div = document.createElement("div");

html_div.innerHTML = html_text;

all_elements = html_div.getElementsByTagName("*");

}

if ((heading_level==null) || (heading_level==""))

heading_level=3;

if (show_level==null)

show_level=0;

var hopen="<h"+heading_level+">";

var hclose="</h"+heading_level+">";

structure = "";

first_level = 0;

level_no = 0;

this_level = 0;

last_level = 0;

current_level = 0;

for (i = 0; i < all_elements.length; i++) {

h_message = "";

element_text = "";

a = all_elements[i];

if (document.all) {

element_text = a.innerText;

} else {

element_text = a.textContent;

}

node_name = all_elements[i].nodeName;

if (node_name == "H1" || node_name == "H2" || node_name == "H3" || node_name == "H4" || node_name == "H5" || node_name == "H6") {

level_no++;

this_level = parseInt(all_elements[i].nodeName.substring(1, 2));

if (level_no == 1)

first_level = this_level;

if (show_level==1)

element_text+=" ("+this_level+")";

// if we are bookmarking the contents

if (do_bookmarks==1)

element_text = "<a href='#generated_link_" + i + "'>" + element_text + "</a>";

if (this_level == last_level) {

if (first_level == this_level)

structure += hopen + element_text + hclose;

else

structure += "<li>" + element_text + "</li>";

}

else if (this_level > last_level) {

current_level++;

difference = this_level - last_level;

if (difference > 1) {

h_message = " (bad heading structure)</li>";

}

if (first_level == this_level)

structure += hopen + element_text + hclose;

else

structure += "<ul><li>" + element_text + h_message + "</li>";

}

else if (this_level < last_level) {

difference = last_level - this_level;

for (z = 0; z < difference; z++) {

current_level--;

structure += "</ul>";

}

structure += "</ul>";

if (current_level < 0)

structure += "<li>" + element_text + "</li> (bad heading structure)";

else {

if (first_level == this_level)

structure += hopen + element_text + hclose;

else

structure += "<ul><li>" + element_text + "</li>";

}

if (do_bookmarks == 1) {

var lnk = document.createElement("a");

lnk.name = "generated_link_" + i;

lnk.id = "generated_link_" + i;

all_elements[i].appendChild(lnk);

}

last_level = this_level;

}

for (z = 0; z < current_level; z++) {

structure += "</ul>";

}

return structure;

}

You’ll want a target div for the table of contents somewhere on your page:

[brushxml]

&lt;div id='table_of_contents_target'&gt;Your TOC will go here&lt;/div&gt;

[brushxml]

Then call the function at the end of a page or stick a window.onload function in:

[brushjs]

window.onload=function() {

	document.getElementById("table_of_contents_target").innerHTML = get_my_navigation(1, '', 1, 3, 0);

}

[brushjs]

window.onload=function() {

document.getElementById("table_of_contents_target").innerHTML = get_my_navigation(1, '', 1, 3, 0);

}

Parameters

The parameters are pretty straight forward:

use_body: 1 will take everything in the body of the document; 0 if you are going to pass HTML in
html_text: The HTML you want it to use if you aren’t using the whole document. If you aren’t passing any in, just leave it blank – “”. You can just pass in the html of a particular div like this: document.getElementById(“a_div”).innerHTML. I should probably change it so you can just pass a div ID in..
do_bookmarks: 1 if you want the document map hyper-linked to the headings. (This will add anchors at the heading elements).; 0 will just give a plain text listing.
heading_level: The first item in the listing will be a heading, followed by nested lists. This sets the heading level you want it to be. (most likely 2 or 3). The default is 3.
show_level: If you set this to 1 it will add the heading level to the end of the link (like in the example on this page.; 0 will leave it off

It would probably be better to replace use_body with an element ID and do it that way, but I haven’t got round to doing that yet..

JavaScript document map

Parameters

Example..

A heading

A sub heading

Another sub heading

Another sub heading

Another sub heading

Another heading

Another sub heading

A bad heading structure

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