Break out of and oTrans_labor Adapter method

I have this small block of code that I want to catch a null or empty string in a text box called SerialNumberTB and exit out of the method after setting focus to the box that needs updating. Any ideas how to break or return to the form after the SerialNumberTB.Focus(); line?

         {
        // ** Argument Properties and Uses **
        // ** args.MethodName **
        // ** Add Event Handler Code **
  
           EpiDataView test = (EpiDataView)oTrans.EpiDataViews["Start"];
	
	  if(test.HasRow)
	  {
          string testJobNum = test.dataView[test.Row]["JobNum"].ToString();
          string ckSerial = test.dataView[test.Row]["ShortChar01"].ToString();
          string pJob = "P-";
          string hJob = "H-";
          string value = "";
          if (testJobNum.Contains(pJob) || testJobNum.Contains(hJob)); 
          {
			bool serialCk = String.IsNullOrEmpty(SerialNumberTB.Value.ToString());
            if (serialCk)
            {
                MessageBox.Show("Please input a valid Serial Number for this Assembly.");
	        SerialNumberTB.Focus();
                //need some code here to break out of thei
            }
               
          }
        }```

Hello @Miker , did you get anywhere on this? I’m trying to figure out the same thing on qty adj, wanting to stop execution if the reference field is blank on reason codes that require a reference

No Ended up doing something different. Sorry.