Note: Advice in this article will only work for DotNetBrowser 1.
See the corresponding article for DotNetBrowser 2 here.

In DotNetBrowser 1.8.2 the JavaScript context events have been added:


  • ScriptContextCreated - indicates that JavaScript context has been created.
  • ScriptContextDestroyed - indicates that JavaScript context has been destroyed.


The ScriptContextCreated event can be used to execute any JavaScript code before the web page JavaScript is executed:

C#

browser.ScriptContextCreated += (sender, args) =>
{
  browser.ExecuteJavaScriptAndReturnValue(args.Context.FrameId, @"
    screen = new function() {
    this.width = 100;
  }");
};

VB.NET

AddHandler browser.ScriptContextCreated, Sub(sender, args) 
    browser.ExecuteJavaScriptAndReturnValue(args.Context.FrameId, "
      screen = new function() {
      this.width = 100;
    }")
End Sub


Both events are processed synchronously, blocking JavaScript execution on the web page. It is not recommended to put the long-running code in the corresponding event handler, because this will affect web page loading and displaying performance.