点击下载此附件

效果图：

方法一：用菜单上的条件格式工具，如下图

方法二：在窗体加载事件在加如下代码
Private Sub Form_Load()
'sfrChild是子窗体控件的名称,me.sfrChild.Form即代表子窗体
    SetMyFormat Me.sfrChild.Form, "编号之计数>1"
End Sub

Function SetMyFormat(frm As Form, tj As String) As Boolean
    Dim ctl As Control
    Dim fcd As FormatCondition
    For Each ctl In frm.Controls
    '如果控件是文本框或组合框
        If ctl.ControlType = acTextBox or ctl.ControlType = acComboBox Then
            intCount = 0
            '清除条件格式
            ctl.FormatConditions.Delete
            '添加条件格式
            ctl.FormatConditions.Add acExpression, acEqual, tj
            Set fcd = ctl.FormatConditions.Item(intCount)
            '具体的格式显示
            With fcd
                .BackColor = 255    '背景色红色
                .ForeColor = 0    '前景色黑色
            End With
        End If
    Next ctl
    SetMyFormat = True
    Set ctl = Nothing
    Set fcd = Nothing
End Function