请教NULL值问题？

[xiaoping832]

怎样才能让已经允许为空的字段显示时不提示“无效null值，错误94”
Text1.Text = mar.Fields(0)
Text4.Text = mar.Fields(1)
Combo1.Text = mar.Fields(2)
Text5.Text = mar.Fields(3)
Text8.Text = mar.Fields(4)
Text6.Text = mar.Fields(5)
Text2.Text = mar.Fields(6)
Text7.Text = mar.Fields(7)
Text3.Text = mar.Fields(8) '
---8已经定义为[comment] [varchar] (200) collate chinese_prc_ci_as null)