删除功能这哪错啦？

Dim strsql As String = "select * from message1 where caption=" & Session("caption") & ""
Dim da As New SqlDataAdapter(strsql, Conn)
Conn.Open()
da.Fill(ds, "message1")
Dim deletesql = "Delete from message1 where caption=" & Session("caption") & ""
Dim comm As New SqlCommand(deletesql, Conn)
comm.ExecuteNonQuery()
ds.Tables("message1").Clear()
Dim str3 As String = "select * from message1 "
da = New SqlDataAdapter(str3, Conn)
da.Fill(ds, "message1")
Dim dv As DataView = ds.Tables("message1").DefaultView
DataGrid1.DataSource = dv
DataGrid1.DataBind()
Response.Write("<script defer>alert('处理成功');</script>")
Conn.Close()