首先看这个帖子，了解插件如何开发 https://wenku.my7c.com/link/s/ltfaZ，这个帖子里已经有源码了，再这个源码基础上添加文中代码编译后放到k3erp目录即可查看效果；

效果图

首先找到自定义字段再表头的位置

添加代码，加载单据事件

Private Sub m_BillTransfer_LoadBillEnd(ByVal ShowType As Long)   

 If m_BillTransfer.SaveVect Is Nothing Then        

If lngUserDatePlace > 0 Then            

m_BillTransfer.SetHead lngUserDatePlace, ""       

 End If    

End If 

End Sub 

Private Sub m_BillTransfer_NewBillEnd()     

If lngUserDatePlace > 0 Then        

m_BillTransfer.SetHead lngUserDatePlace, ""    

End If 

End Sub

Private Function GetHeadCtlOrderByFieldName(ByVal strFieldName As String) As Long    

    Dim i As Long    

    For i = 1 To UBound(m_BillTransfer.HeadCtl)        

        If UCase(Trim(m_BillTransfer.HeadCtl(i).FieldName)) = UCase(Trim(strFieldName)) Then            

            GetHeadCtlOrderByFieldName = i            

            Exit Function        

        End If    

    Next i    

    GetHeadCtlOrderByFieldName = 0 

End Function