Parallelcoding.com

function replaceTerms(){	
	var searchArray = new Array("favors","labors","colors","favor","labor","color");
	var replaceArray = new Array("favours","labours","colours","favour","labour","colour");
 
	if (!document.body || typeof(document.body.innerHTML) == "undefined") {
		//alert("Sorry, for some reason the text of this page is unavailable. Searching will not work.");
		return false;
	}
 
	var bodyText = document.body.innerHTML;
	for (var i = 0; i < searchArray.length; i++) {
		bodyText = doReplace(bodyText, searchArray[i], replaceArray[i]);
	}
 
	//document.body.innerHTML = bodyText;
	return true;
}
 
function doReplace(bodyText, searchTerm, replaceWith) {
 
	// 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();
	var lcBodyText = bodyText.toLowerCase();
 
	while (bodyText.length > 0) {
 
		//Get index of search term
		i = lcBodyText.indexOf(lcSearchTerm, i+1);
 
		//if we can't fine it, replace the newText with the BodyText and return
		if (i < 0) {
			newText += bodyText;
			bodyText = "";
		} else {
 
			// 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)) {
 
					//Get Ascii Representation
					var	charCode = bodyText.charAt(i).charCodeAt(0);
 
					//Is this uppercase
					var isUpper = (charCode >= 65 && charCode <= 90);
 
					//Do replacing
					if(isUpper){
						newText += bodyText.substring(0, i) +  replaceWith.charAt(0).toUpperCase() + replaceWith.substr(1) + " ";
					}else{
						newText += bodyText.substring(0, i) +  replaceWith + " ";
					}
					bodyText = bodyText.substr(i + searchTerm.length);
					lcBodyText = bodyText.toLowerCase();
					i = -1;
				}
			}
		}
	}
 
	return newText;
}

Private Function doReplace(ByVal bodyText As String, ByVal searchTerm As String, ByVal replaceWith As String) As String
	Private Function doReplace(ByVal bodyText As String, ByVal searchTerm As String, ByVal replaceWith As String) As String
	Dim newText As String = ""
	Dim i As Integer = -1
	Dim lcSearchTerm As String = searchTerm.ToLower()
	Dim lcBodyText As String = bodyText.ToLower()
 
	While bodyText.Length > 0
		'Get the index of the search term
		i = lcBodyText.IndexOf(lcSearchTerm, i + 1)
 
		'If it isn't there, just return
		If i < 0 Then
			newText += bodyText
			bodyText = ""
		Else
			'Avoid tags
			If bodyText.LastIndexOf(">", i) >= bodyText.LastIndexOf("<", i) Then
				'Avoid scripts
				If lcBodyText.LastIndexOf("/script>", i) >= lcBodyText.LastIndexOf("<script", i) Then
					'Is the first character uppercase?
					Dim isUpper As Boolean = Char.IsUpper(bodyText.Chars(i))
 
					'If it is, then capitalize the replacement
					If isUpper Then
						newText += bodyText.Substring(0, i) + Char.ToUpper(replaceWith.Chars(0)) + replaceWith.Substring(1) + " "
					Else
						newText += bodyText.Substring(0, i) + replaceWith + " "
					End If
 
					'Truncate body text
					bodyText = bodyText.Substring(i + searchTerm.Length())
 
					'Reset current text
					lcBodyText = bodyText.ToLower()
					i = -1
				End If
			End If
		End If
	End While
 
	Return newText
End Function