function validateMaterialExtension()
{
   var objSelector = document.getElementById('materialtype')
   var objOverig = document.getElementById('materialextensionfield')
   var strMaterial = objSelector.options[objSelector.selectedIndex].value;
   var strMaterialExtension = objOverig.value;

   if ((strMaterial == 'Overig') && (strMaterialExtension.length == 0))
   {
      alert('You have not filled in the preferred type of fabric.');
      objOverig.focus();
      return false;
   }
   else
   {
      return true
   }
} 


function submitSearchForm()
{
   var strValue = document.searchform.searchvalue.value;

   if (strValue.length !== 0)
   {   
      document.searchform.submit();
   }
   else
   {
      alert('You have not filled in any search criteria.'); 
      document.searchform.searchvalue.focus();
   }
}



function validateImageUpload()
{
   var objDrawing = document.getElementById('tekening0')
   var objMaatvoeringLengte = document.getElementById('tekening0')
   var objMaatvoeringOppervlak = document.getElementById('maatvoeringOppervlak')
   var objMaatvoeringOmtrek = document.getElementById('maatvoeringOmtrek')
   var objMaatvoeringAdditioneel = document.getElementById('maatvoeringAdditioneel')

   if ((objMaatvoeringLengte.value.length == 0) && (objMaatvoeringOmtrek.value.length == 0) && (objMaatvoeringOppervlak.value.length == 0) && (objMaatvoeringAdditioneel.value.length == 0) && (objDrawing.value.length == 0))
   {
      alert('You have not filled in the preferred size in the previous screen. Please add one or more drawings in this screen. We can reduce the sizes of this drawing.');

      return false;
   }

   return true;
}