Mehul Harry's DevExpress Blog

// Event handler
function OnCustomCommand(s, e) {
    if (e.commandName == "ChangeCase")
        ChangeCase(e.parameter);
}
 
// Change case functionality
function ChangeCase(value) {
    var selection = HtmlEditor.GetSelection();
    var selectedElements = selection.GetElements();
    var textNodes = findAllTextNodes(selectedElements);
    for (var i = 0; i < textNodes.length; i++) {
        switch (value) {
            case "capitalize":
                var sentenceEndExp = /\.+\s*$/;
                var emptyStringExp = /\s*/;
                var prevText = getPreviousText(textNodes[0]);
                var capitalizeFirstLetter = emptyStringExp.test(prevText) || sentenceEndExp.test(prevText);
                textNodes[i].nodeValue = capitalize(textNodes[i].nodeValue.toLowerCase(), capitalizeFirstLetter);
                break;
            case "lowercase":
                textNodes[i].nodeValue = textNodes[i].nodeValue.toLowerCase();
                break;
            case "uppercase":
                textNodes[i].nodeValue = textNodes[i].nodeValue.toUpperCase();
                break;
            case "camelize":
                textNodes[i].nodeValue = camelize(textNodes[i].nodeValue.toLowerCase());
                break;
        }
    }
    HtmlEditor.ExecuteCommand(ASPxClientCommandConsts.SAVESTATEUNDOREDOSTACK_COMMAND, null);
}
function findAllTextNodes(elements) {
    var nodes = [];
    if (elements) {
        for (var i = 0; i < elements.length; i++) {
            if (elements[i].nodeType == 3)
                nodes.push(elements[i]);
            else
                nodes = nodes.concat(findAllTextNodes(elements[i].childNodes));
        }
    }
    return nodes;
}
function getPreviousText(element) {
    var prevElement = element.previousSibling;
    return (prevElement && prevElement.nodeType == 3) ? getPreviousText(prevElement) + prevElement.nodeValue : "";
}
function capitalize(text, capitalizeFirstLetter) {
    var text = text.replace(/(\.|\?|\!)+\s+\S+/g, function (word) {
        return word.charAt(0) + " " + word.charAt(2).toUpperCase() + word.substring(3).toLowerCase();
    });
    if (capitalizeFirstLetter)
        text = text.replace(/\S+/, function (word) {
            return word.charAt(0).toUpperCase() + word.substring(1).toLowerCase();
        });
    return text;
}
function camelize(text) {
    return text.replace(/\S+/g, function (word) {
        return word.charAt(0).toUpperCase() + word.substring(1).toLowerCase();
    });
}