Hi Simplicio,
you can use response.write:

Response.Write("<script>javascript:window.open('download.aspx')</script>")

change the url as needed.
HTH
Franco

>Hi I want to envoke the java script "window.open()" in the server side command button. Do you have any Idea how to do this? I want to create a download page with a Query String parameter from Data Time picker.
>

>  this.btnDownload.OnClientClick="windows.open(download.aspx?FromDate=" + DatePicker.SelectedDate + ")"
>   // Something like this
>
>

>
>
>And I want to open a new page with Parameters every time the button was click. Server.redirect() is not suitable to my need. I believe Javascript Windows.Open() solves the issue except that I cannot get the property of the custom Control in ASP.NET server side.
>
>Thank you
>
>Simiplicio