// Check to see if user enters his details.
function validateField( formName ) {
   // Initialise local variables.
   var aFormName    = formName;
   var aEmptyField  = false;
   var aCorrect     = false;
   var aErrMessage  = "";
   var aEmailFilter = /^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i;   
   
   // Check Name Field.
   if( aFormName.txtfldName.value == "" ) {
      aEmptyField  = true;
      aErrMessage  = "Please fill in your Name.\n";
   }
   
   // Check Contact No Field.
   if( aFormName.txtfldContactNo.value == "" ) {
      aEmptyField  = true;
      aErrMessage += "Please fill in your 8 digit numeric Contact No.\n";
   } else {
      var aStrNumber    = aFormName.txtfldContactNo.value;
      var aStrNumberLen = aStrNumber.length;
      
      if( aStrNumberLen != 8 ) {
         aEmptyField  = true;
         aErrMessage += "Please fill in your 8 digit numeric Contact No.\n";      	
      } else {
         for( var i=0; i!=aStrNumberLen; i++ ) {
            var aChrChar = aStrNumber.substring( i, i+1 );
            
            if( aChrChar < "0" || aChrChar > "9" ) {
               aEmptyField  = true;
               aErrMessage += "Please fill in your 8 digit numeric Contact No.\n";
            }
         }
      }
   }
   
   // Check Email Field.
   if( aFormName.txtfldEmail.value == "" ) {
      aEmptyField = true;
      aCorrect    = false;
   } else {
      if( aEmailFilter.test( aFormName.txtfldEmail.value ) ) {
         aCorrect = true;
      } else {
         aEmptyField = true;
         aCorrect    = false;
      }
   }
   
   if( !aCorrect ) {
      aErrMessage += "Please enter a valid Email Address.\n";
   }
   
   // Check Message Field.
   if( aFormName.txtareaEnquiry ) {
      if( aFormName.txtareaEnquiry.value == "" ) {
         aEmptyField  = true;
         aErrMessage += "Please fill in your Message.";
      }
   }
   
   // Check Program Options Field.
   if( aFormName.radbutProgram ) {   	
      if( aFormName.radbutProgram[0].checked || aFormName.radbutProgram[1].checked || aFormName.radbutProgram[2].checked || aFormName.radbutProgram[3].checked || aFormName.radbutProgram[4].checked || aFormName.radbutProgram[5].checked || aFormName.radbutProgram[6].checked ) {
      } else {
         aEmptyField  = true;
         aErrMessage += "Please select one Program Option to attend.\n";      	
      }
   }
   
   if( aEmptyField ) {
      alert( aErrMessage );
   }
   
   return aEmptyField;
}

function checkField( formName, actionName ) {
   var aErr = false;
   var aFormName   = formName;
   var aActionName = actionName;
   
   aErr = validateField( aFormName );

   if( !aErr ) {
      aFormName.action = aActionName;
      aFormName.method = "post";
      aFormName.submit();
   } 
}