Show Server Side Yes No Confirmation Box using AJAX ScriptManager in ASP.Net

Hi

I am throwing a alert box using scriptmanager like this based on some condition.

ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "alertMessage", "alert('Would you like to be put on the wait list?')", true);

But it has only "ok" button. Is there a way to display a message box which has yes/no buttons so that I want to check some more conditions in the code behind. Appreciate some help.

something like this.

DialogResult result = MessageBox.Show("Do you wanna do something?", "Warning", 
MessageBoxButtons.YesNoCancel, MessageBoxIcon.Warning);
if(result == DialogResult.Yes)
{
   //code for Yes
}
else if(result == DialogResult.No)
{
  //code for No
}
else if (result == DialogResult.Cancel)
{
  //code for Cancel
}