function ToggleButton(button, validationGroup)
{
   if (typeof(Page_Validators) == "undefined")
   {
        DisableButton(button);
   }
   
   if (typeof(Page_ClientValidate) == 'function') 
   {
         Page_ClientValidate(validationGroup);                 
      
         if(Page_IsValid)
         {  
            DisableButton(button)       
         }
   }
   else
   {
        DisableButton(button);
   }
}


function DisableButton(button)
{   
    div1 = window.document.getElementById(button.id + 'Show');
    div2 = window.document.getElementById(button.id + 'Hide');

    div1.style.display = "none";
    div2.style.display = "block";
}