rst.update问题，莫见笑

本人菜鸟，运行时老是提示rst.update问题。求指教。谢谢@！

Private Sub cmdsave_Click()

Dim rst As Object
Dim strSQL As String
Dim MaxID As String
Dim currentID As String
Dim strFrm As String
If IsNull(Me.TXTYGXM) Then
MsgBox "请输入员工姓名!", vbCritical, "提示"
Me.TXTYGXM.SetFocus
Exit Sub
End If
MaxID = DMax("[ygID]", "tblCodeyg")
currentID = "Y" & Format(Val(Right$(MaxID, 2) + 1), "00")
strSQL = "select*from tblCodeyg"
Set rst = CurrentDb.OpenRecordset(strSQL, dbOpenDynaset)
rst.AddNew
rst!ygID = currentID
rst!ygID = Me.TXTYGXM
rst.Update
rst.Close
Set rst = Nothing
Me.TXTYGXM = Null
DoEvents
strFrm = Form_frmYg_sg_Main!frmChild.SourceObject
Form_frmYg_sg_Main!frmChild.SourceObject = strFrm
MsgBox "保存成功!", vblnformation, "消息"
End Sub