CurrentChanged事件:
If Forms("窗口1").Opened And e.Table.Current IsNot Nothing Then
Dim tx As WinForm.TextBox = Forms("窗口1").Controls("TextBox1")
Dim dr As DataRow
dr = DataTables("表A").Find("第一列 = '" & e.Table.Current("第一列") & "' And [_identify] < " & e.Table.current("_Identify"),"[_Identify] Desc")
If dr IsNot Nothing Then
Forms("窗口1").Controls("TextBox1").value = dr("第二列")
End If
End If