主题：判断同一行中两个字符串是否相同

如果写在datacolchanging事件，改成

if e.datacol.name = "新手机号码" then 

    if e.newvalue isnot nothing then

         dim s1 as string = e.datarow("旧手机号码" )

         dim s2 as string = e.newvalue

              if  s1 = s2

                 e.cancel = true

                messagebox.show("手机号码重复") 

              end if

     end if

end if