Javascript to search backwards and forwards

[adithy]

Hi friends,
The following MODIFIED javascript code searches and highlights occurances of searchedTerms in a XML page. But i need to use two buttons "next" and "previous". If i click on the "next" it wil highlight only one searchTerm at once. (NEXT BOTTON WORKING FINE). But i couldn't find the solution for "backward search". Please anyone could help me to do this. Please, it's urgent. Any reply will be appreciated.(IT'S WORKING IN SAFARI.)

/*
* This is the function that actually highlights a text string by
* adding HTML tags before and after all occurrences of the search
* term. You can pass your own tags if you'd like, or if the
* highlightStartTag or highlightEndTag parameters are omitted or
* are empty strings then the default <font> tags will be used.
*/

var MyApp_SearchResultCount = 0;
var i = -1;
var newText = "";
var lcBodyText="";

//var searchTerm = 0;
function doHighlight(bodyText, searchTerm, highlightStartTag, highlightEndTag)
{
// find all occurences of the search term in the given text,
// and add some "highlight" tags to them (we're not using a
// regular expression search, because we want to filter out
// matches that occur within HTML tags and script blocks, so
// we have to do a little extra validation)
//var newText="";
//var i = -1;

var lcSearchTerm = searchTerm.toLowerCase();
lcSearchTerm = searchTerm.toLowerCase();

if(lcBodyText ==""){
lcBodyText = bodyText.toLowerCase();
}
if(lcSearchTerm =="")
{
alert('Not Found');
}

i = lcBodyText.indexOf(lcSearchTerm, i+1);

if(i < 0) {
newText = bodyText;
bodyText ="";
}
else
{
//check whether the button is clicked for the first time
//i.e newText is empty
if(newText == ""){
// skip anything inside an HTML tag
if (bodyText.lastIndexOf(">", i) >= bodyText.lastIndexOf("<", i)) {
// skip anything inside a <script> block
if (lcBodyText.lastIndexOf("/script>", i) >= lcBodyText.lastIndexOf("<script", i)) {

newText += bodyText.substring(0, i) + highlightStartTag + bodyText.substr(i, searchTerm.length) + highlightEndTag;
bodyText = bodyText.substr(i + searchTerm.length);
lcBodyText = bodyText;

i = -1;
}
}

}else{
// skip anything inside an HTML tag
if (lcBodyText.lastIndexOf(">", i) >= lcBodyText.lastIndexOf("<", i)) {
// skip anything inside a <script> block
if (lcBodyText.lastIndexOf("/script>", i) >= lcBodyText.lastIndexOf("<script", i)){
newText += lcBodyText.substring(0, i) + highlightStartTag + lcBodyText.substr(i, searchTerm.length) + highlightEndTag;
bodyText = lcBodyText.substr(i + searchTerm.length);
lcBodyText = bodyText;

i = -1;
}
}
}//End newtext=="" if else
}

return newText + bodyText ;
}

/*
* This is sort of a wrapper function to the doHighlight function.
* It takes the searchText that you pass, optionally splits it into
* separate words, and transforms the text on the current web page.
* Only the "searchText" parameter is required; all other parameters
* are optional and can be omitted.
*/
function highlightSearchTerms(searchText, treatAsPhrase, warnOnFailure, highlightStartTag, highlightEndTag)
{
// if the treatAsPhrase parameter is true, then we should search for
// the entire phrase that was entered; otherwise, we will split the
// search string so that each word is searched for and highlighted
// individually
if (treatAsPhrase) {
searchArray = [searchText];
} else {
searchArray = searchText.split(" ");
}
var bodyText = document.body.innerHTML;
for (var i = 0; i < searchArray.length; i++) {
bodyText = doHighlight(bodyText, searchArray[i], highlightStartTag, highlightEndTag);

}
//display the search text within the text box for next/previous
//button click

document.body.innerHTML = bodyText;
document.getElementById('searchme').value=searchArray[0];
return true;
}


/*
* This displays a dialog box that allows a user to enter their own
* search terms to highlight on the page, and then passes the search
* text or phrase to the highlightSearchTerms function. All parameters
* are optional.
*/
function searchPrompt(defaultText, treatAsPhrase)
{
// This function prompts the user for any words that should
// be highlighted on this web page
if (!defaultText) {
defaultText = "";
}

// we can optionally use our own highlight tag values
highlightStartTag = "<span name= 'highlighted_text' style='color:blue; background-color:yellow;'>";
highlightEndTag = "</span>";



/*if (treatAsPhrase) {
promptText = "Please enter the phrase you'd like to search for:";
} else {
promptText = "Please enter the words you'd like to search for:";
}*/


searchText =defaultText; //prompt(promptText);
//set the value iniside search text box to be
//null so that it may not be highlighted
document.getElementById('searchme').value="";
return highlightSearchTerms(searchText, treatAsPhrase, true, highlightStartTag, highlightEndTag);
}


/*
* This function takes a referer/referrer string and parses it
* to determine if it contains any search terms. If it does, the
* search terms are passed to the highlightSearchTerms function
* so they can be highlighted on the current page.
*/
function highlightGoogleSearchTerms(referrer)
{
// This function has only been very lightly tested against
// typical Google search URLs. If you wanted the Google search
// terms to be automatically highlighted on a page, you could
// call the function in the onload event of your <body> tag,
// like this:
// <body onload='highlightGoogleSearchTerms(document.referrer);'>

//var referrer = document.referrer;
if (!referrer) {
return false;
}

}
function MyApp_RemoveAllHighlightsXml() {
SearchResultCount = 0;
bodyText = "";
var remove=document.getElementsByTagName("span");
if (remove) {
for (var i=remove.length-1;i>-1;i--) {
if (remove[i].getAttribute("name")=="highlighted_text") {
var s=remove[i].innerHTML;
var otxt=document.createTextNode(s)
remove[i].parentNode.insertBefore(otxt,remove[i]);
remove[i].parentNode.removeChild (remove[i]);
}
}
}
}