ASP.NET Custom Server Controls: Cute ASP.NET TextBox with Help Tips - Briefly understanding the JavaScript implementation

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As you understand by now, my control needs to work with JavaScript (to display help tips dynamically), so I implemented each of those JavaScripts as separate methods which together can be registered to the page within the "AddAttributesToRender” method.  The following are the four core methods which emit their respective JavaScripts:

getJS4GotFocus
getJS4LostFocus
getJS4MouseOver
getJS4MouseOut

All of the above user-defined methods (which emit JavaScripts), together with the following code-fragment, made it convenient for me to achieve what I expected:

'emit javascript only at run-time
        If Not IsDesignTime Then
            'focus events
            If Me.ShowHelpTipsOnFocus Then
                If Not Page.IsStartupScriptRegistered(Me.UniqueID
& "_GotFocus") Then
                    Page.RegisterStartupScript(Me.UniqueID &
"_GotFocus", getJS4GotFocus(Me.UniqueID))
                End If
                If Not Page.IsStartupScriptRegistered(Me.UniqueID
& "_LostFocus") Then
                    Page.RegisterStartupScript(Me.UniqueID &
"_LostFocus", getJS4LostFocus(Me.UniqueID))
                End If
                writer.AddAttribute("onFocus", Me.UniqueID &
"_GotFocus();")
                writer.AddAttribute("onBlur", Me.UniqueID &
"_LostFocus();")
            End If
            'mouse events
            If Me.ShowHelpTipsOnMouse Then
                If Not Page.IsStartupScriptRegistered(Me.UniqueID
& "_MouseOver") Then
                    Page.RegisterStartupScript(Me.UniqueID &
"_MouseOver", getJS4MouseOver(Me.UniqueID))
                End If
                If Not Page.IsStartupScriptRegistered(Me.UniqueID
& "_MouseOut") Then
                    Page.RegisterStartupScript(Me.UniqueID &
"_MouseOut", getJS4MouseOut(Me.UniqueID))
                End If
                writer.AddAttribute("onMouseOver", Me.UniqueID &
"_MouseOver();")
                writer.AddAttribute("onMouseOut", Me.UniqueID &
"_MouseOut();")
            End If
        End If

Remarks

This control has been developed just to initiate and show the power of custom controls to control everything right from the beginning through to the end, including client-side JavaScript emission.  I didn’t quite implement all of the features of original ASP.NET Textbox control (as it would take a series of articles).  You just need to learn a few more interfaces and methods to implement all of the original features along with your own features. 

I leave it to the developers to further enhance the same control.  The areas for improving the control would include eventing, better JavaScript for validation, data-binding, and so on.  Good luck.

Any comments, suggestions, bugs, errors, feedback etc. are highly appreciated at jag_chat@yahoo.com.

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Comments On: ASP.NET Custom Server Controls: Cute ASP.NET TextBox with Help Tips

· Hello guys, Cute control...further enhanced..., any suggestions to enhance it?    · good article, the code is kinda hard to read though    · thanks for the comment. You can download the sample to go through the code in a...   >>> Post your comment now!