Useful Custom Controls for WebForms

I've been lucky enough to have quite a bit of exposure to Custom Controls of late and thought that I'd make a short note about the usefulness of them.

1.) Andy Smith's DialogWindow

I had to use several pop-up windows to allow users to edit, search, etc and, on close of the pop-up I needed to be able to do a controlled postback of the opener so that I could reset the state of some UserControls on the page. Initially, I had been just using custom javascripts to send arguments back to the opener and re-painting some of the UI with client script. This method left me short because some of the re-painting actually required a call to the db to get the details of newly inserted records.

The DialogWindow allows me to close a child pop-up with a method that also allows me to send results to the opener like so:

    ' perform some db operations
    retVal = SqlHelper.ExecuteScalar(...)
    
    ' close the pop-up and send the database results to the opener window
    Me.Close( retVal.ToString )

The Close() method is appended to the Page by deriving from MetaBuilders.WebControls.DialogPage.

Back in the opener a postback is raised and the postback results can be retrieved in the DialogClosed event handler for the DialogWindow:

    Private Sub MyDialog_DialogClosed(ByVal sender As Object, ByVal e As DialogResultEventArgs) Handles MyDialog.DialogClosed
        
        ' retreive the database results in the parent
        Dim r As String = e.Results
        
    End Sub

One thing that I did do differently to the documentation for that control is to call the Dialog.Open clientside function directly - as opposed to using a DialogOpenButton. I did this so that I could send QueryString args to the window that I'm opening:

    function OpenPage()
    {
        var baseUrl = "http:\/\/localhost\/WebSite\/SubForms\/frmPopUp.aspx"
        var qString = "?mode=edit&tc=2&vc=LP02%20%20&mc=V2&oi=16441&os=8VA00%26Y%232&dt=TABLE_DD_SS"
        var opts = "width=630,height=550,resizable=yes,status=yes,scrollbars=yes" ; 
        MetaBuilders_DialogWindow_OpenDialog( baseUrl + qString, 'MyDialog', opts )
    }

2.) Denis Bauer's DynamicControlsPlaceholder Control

In the same app. (as mentioned above) I had to build an engine that would build dynamic forms based on definitions stored in various storage medium. The benefit in using this control is that it: "behaves like a placeholder but additionally handles recreating dynamic controls on subsequent requests". The control not only handles the re-creation of dynamically added controls on postback but also deals with the ViewState restoration for them as well.