Тут описан такой пример:
Код:
protected void Button1_Click(object sender, EventArgs e)
{
AxUrlMenuItem menuItem = new AxUrlMenuItem("EPDocuGet");
DataSetViewRow row = dsEPCustInvoiceJournalInfo.GetDataSet().DataSetViews[0].GetCurrent();
AxTableContext context = AxTableContext.Create(row.GetDefaultTableDataKey(row.DataSetView.Metadata.RootDataSource));
menuItem.MenuItemContext = context;
//Response.Redirect(menuItem.Url.ToString());
string downloadURL = "window.open('" + menuItem.Url.ToString() + "', '_blank', '' );";
ScriptManager.RegisterStartupScript(this, typeof(string), "OPEN_WINDOW", downloadURL, true);
}