How2 save changes to dataSET made at runtime?
Posted: Fri 28 Nov 2008 03:47
I have a database with no datatable. I add a datatable (temp1) and 3 columns (column1, column2 and column3) to that datatable (by setting the CommandText property of a Command object called m_cmd and then invoking the ExecuteNonQuery method.) (Also, m_conn is the connection that m_cmd uses to talk to the database.)
I then add the same datatable & columns to the corresponding typed dataset (m_ds) which I created at design time using the Devart Dataset Wizard. These are both done at runtime programatically by clicking the button called m_createTableButton.
I exit my application and re-start it. The database retains those changes (the new datatable & its new columns are still there), but the dataset does not. It's still in the original form, as if I'd never made those changes.
How do I save those dataset changes before exiting the app? Does it have something to do with the WriteXmlSchema method of the m_ds dataset?
-------REFERENCE CODE
Private Sub m_createTableButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles m_createTableButton.Click
'Create a new table & 3 columns in the dataBASE
m_cmd.CommandText = "CREATE TABLE temp1 (column1 character varying(10), column2 character varying(10), column3 character varying(10))"
m_conn.Open()
m_cmd.ExecuteNonQuery()
m_conn.Close()
'Now create the same table & 3 columns in the dataSET
Dim temp1 As DataTable = New DataTable("temp1")
temp1.Columns.Add("column1", GetType(System.Char))
temp1.Columns.Add("column2", GetType(System.Char))
temp1.Columns.Add("column3", GetType(System.Char))
m_ds.Tables.AddRange(New DataTable() {temp1})
End Sub
I then add the same datatable & columns to the corresponding typed dataset (m_ds) which I created at design time using the Devart Dataset Wizard. These are both done at runtime programatically by clicking the button called m_createTableButton.
I exit my application and re-start it. The database retains those changes (the new datatable & its new columns are still there), but the dataset does not. It's still in the original form, as if I'd never made those changes.
How do I save those dataset changes before exiting the app? Does it have something to do with the WriteXmlSchema method of the m_ds dataset?
-------REFERENCE CODE
Private Sub m_createTableButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles m_createTableButton.Click
'Create a new table & 3 columns in the dataBASE
m_cmd.CommandText = "CREATE TABLE temp1 (column1 character varying(10), column2 character varying(10), column3 character varying(10))"
m_conn.Open()
m_cmd.ExecuteNonQuery()
m_conn.Close()
'Now create the same table & 3 columns in the dataSET
Dim temp1 As DataTable = New DataTable("temp1")
temp1.Columns.Add("column1", GetType(System.Char))
temp1.Columns.Add("column2", GetType(System.Char))
temp1.Columns.Add("column3", GetType(System.Char))
m_ds.Tables.AddRange(New DataTable() {temp1})
End Sub