Question

I am using the System.Windows.Forms.WebBrowser to display XML in a syntax highlighted and easy to traverse format. Whenever I load the XML into the Control, I would like to have all the elements collapsed, is this possible?

Answer 1

This is triggered by the DocumentCompleted event handler.

this was a useful link to help with java script injection:

How to execute custom JavaScript in WebBrowser control?

I used the following code.

    private void CollapseExpandDocument(object sender, WebBrowserDocumentCompletedEventArgs e)
    {
        if (sender == null)
        {
            return;
        }

        try
        {
            WebBrowser me = (WebBrowser) sender;
            HtmlElement head = me.Document.GetElementsByTagName("head")[0];
            HtmlElement scriptEl = me.Document.CreateElement("script");
            IHTMLScriptElement element = (IHTMLScriptElement)scriptEl.DomElement;
            string func = @"
                function collapseDoc() 
                {
                    var className = 'b';
                    var hasClassName = new RegExp('(?:^|\\s)' + className + '(?:$|\\s)');
                    var allElements = document.getElementsByTagName('a');
                    var element;
                    for (var i = 0; (element = allElements[i]) != null; i++) 
                    {
                        var elementClass = element.className;
                        if (elementClass && elementClass.indexOf(className) != -1 && hasClassName.test(elementClass))
                            ch(element.parentElement.parentElement);
                    }
                }";
            element.text = func;
            head.AppendChild(scriptEl);
            me.Document.InvokeScript("collapseDoc");
        }
        catch 
        { 
            //not interested in knowing if the collapse/expand failed...
        }
    }