How to inject Javascript in WebBrowser control?

Question

I've tried this:

string newScript = textBox1.Text; HtmlElement head = browserCtrl.Document.GetElementsByTagName("head")[0]; HtmlElement scriptEl = browserCtrl.Document.CreateElement("script"); lblStatus.Text = scriptEl.GetType().ToString(); scriptEl.SetAttribute("type", "text/javascript"); head.AppendChild(scriptEl); scriptEl.InnerHtml = "function sayHello() { alert('hello') }"; 

scriptEl.InnerHtml and scriptEl.InnerText both give errors:

System.NotSupportedException: Property is not supported on this type of HtmlElement.    at System.Windows.Forms.HtmlElement.set_InnerHtml(String value)    at SForceApp.Form1.button1_Click(Object sender, EventArgs e) in d:\jsight\installs\SForceApp\SForceApp\Form1.cs:line 31    at System.Windows.Forms.Control.OnClick(EventArgs e)    at System.Windows.Forms.Button.OnClick(EventArgs e)    at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)    at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)    at System.Windows.Forms.Control.WndProc(Message& m)    at System.Windows.Forms.ButtonBase.WndProc(Message& m)    at System.Windows.Forms.Button.WndProc(Message& m)    at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)    at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)    at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) 

Is there an easy way to inject a script into the dom?

Answer 1

For some reason Richard's solution didn't work on my end (insertAdjacentText failed with an exception). This however seems to work:

HtmlElement head = webBrowser1.Document.GetElementsByTagName("head")[0]; HtmlElement scriptEl = webBrowser1.Document.CreateElement("script"); IHTMLScriptElement element = (IHTMLScriptElement)scriptEl.DomElement; element.text = "function sayHello() { alert('hello') }"; head.AppendChild(scriptEl); webBrowser1.Document.InvokeScript("sayHello"); 

This answer explains how to get the IHTMLScriptElement interface into your project.