請問遇到了空數據該怎麼處理啊解决方案

請問遇到了空數據該怎麼處理啊？
在讀取過程中可能有些數據時NULL這個時候應該怎麼處理呢？有人說做0處理，能說的詳細一點么？謝謝。

VB code

Private Sub Command4_Click()Dim sc As Integer    If Text1(14).Text = "" Or Text1(15).Text = "" Then 'ÅДàÊÇ·ñÓДµ“þä?ÈëÒÔ¼°ÊÇ·ñÖØÑ}SAVE        sc = MsgBox("Please capture WYKO data first.", vbOKOnly, "Warning : ")    Else            Dim conn As New ADODB.Connection    Dim rs As New ADODB.Recordset    Dim wls_l_num, wls_es_num As String    Dim str1, str2, str3 As String            str1 = "Provider=Microsoft.Jet.OLEDB.4.0;"        str2 = "Data Source=C:\WYKO Data Capture\WYKOData.mdb;"        str3 = "Jet OLEDB:Database Password="                conn.Open str1 & str2 & str3        strSQL = "select * from WYKOData"        rs.Open strSQL, conn, 3, 3                rs.AddNew        rs!Wafer_Number = Text1(6).Text        rs!Min = Text1(0).Text        rs!Max = Text1(1).Text        rs!Average = Text1(3).Text        rs!Range = Text1(4).Text        rs!Std_Dev = Text1(4).Text        rs!S_Number = Text1(5).Text        rs!Meas_Count = Text1(7).Text        rs!Meas_Wafers = Text1(8).Text        rs!Wafers_Lot = Text1(9).Text        rs!Wafer1_meas1 = Text1(10).Text        rs!Wafer1_meas2 = Text1(11).Text        rs!Wafer2_meas1 = Text1(12).Text        rs!Wafer2_meas2 = Text1(13).Text        rs!Wafer_Data = Text1(14).Text        rs!Wafer_Time = Text1(15).Text        rs!Wavelength = Text1(16).Text                rs.Update        rs.Close        conn.Close                MsgBox ("Data Saved.")        Adodc1.Refresh        MSHFG1.Refresh                        For i = 0 To 16                 '·ÀÖ¹ÖØÑ}ä?Èë                Text1(i).Text = ""            Next      End IfEnd Sub