How would I generalise this C# code into a more general method?

Question

I have numerous occurrences of the following in my code:

this.webBrowserCtrl.DocumentCompleted -= new System.Windows.Forms.WebBrowserDocumentCompletedEventHandler(this.LoginScreenLoaded);
this.webBrowserCtrl.DocumentCompleted += new System.Windows.Forms.WebBrowserDocumentCompletedEventHandler(this.AttemptLoginAnalysis);

I wish to remove this and use a simple method that takes 2 inputs - however I don't know what the types would be.

    private void DefineNewDocumentCompletedHandler(TYPEA inputA, TYPEB inputB)
    {

        this.webBrowserCtrl.DocumentCompleted -= new System.Windows.Forms.WebBrowserDocumentCompletedEventHandler(inputA);
        this.webBrowserCtrl.DocumentCompleted += new System.Windows.Forms.WebBrowserDocumentCompletedEventHandler(inputB);

    }

Does anyone know what TYPEA and TYPEB should be? Or another way to accomplish my goal?

Answer 1

Use the delegate type on the input parameters, like this:

private void DefineNewDocumentCompletedHandler(WebBrowserDocumentCompletedEventHandler inputA, WebBrowserDocumentCompletedEventHandler inputB)
{
    this.webBrowserCtrl.DocumentCompleted -= inputA;
    this.webBrowserCtrl.DocumentCompleted += inputB;
}

Example of use:

DefineNewDocumentCompletedHandler(this.LoginScreenLoaded, this.AttemptLoginAnalysis);

The syntax new <delegate type>(<name of method>) is a C# 1.x construct that is now obsolete. From C# 2.0 onwards, you can just specify the name of the method without parentheses, and the compiler will automatically wrap it in a delegate instance for you.

Answer 2

TYPEA and TYPEB are of WebBrowserDocumentCompletedEventArgs

Answer 3

You can also make an extension method of the method described by Christian.

public static void DefineNewDocumentCompletedHandler(this WebBrowser webBrowser, WebBrowserDocumentCompletedEventHandler inputA, WebBrowserDocumentCompletedEventHandler inputB)
{
webBrowser.webBrowserCtrl.DocumentCompleted -= inputA;
webBrowser.webBrowserCtrl.DocumentCompleted += inputB;

}

and use it like

this.webBrowserCtrl.DefineNewDocumentCompletedHandler(this.LoginScreenLoaded, this.AttemptLoginAnalysis);