return primary key from insert command in C#‎

[train_fox]

private int InsertInvoice()
{
SqlCeConnection Conn = new SqlCeConnection(connectString);
SqlCeCommand CMD = new SqlCeCommand();
CMD.Connection = Conn;
CMD.CommandType = CommandType.Text;
CMD.CommandText =
"INSERT INTO InvoiceTB ( " +
"InvoiceDate, InvoiceType, ShopID, ContactID)" +
"VALUES ( " +
"@InvoiceDate, @InvoiceType, @ShopID, @ContactID); "+
"SELECT SCOPE_IDENTITY()";
CMD.Parameters.AddWithValue("@InvoiceDate",Invoice Date);
CMD.Parameters.AddWithValue("@InvoiceType",1);//for buy
CMD.Parameters.AddWithValue("@ShopID",shopID);
CMD.Parameters.AddWithValue("@ContactID",contactID );

Conn.Open();
invoiceID = int.Parse(CMD.ExecuteScalar().ToString());
Conn.Close();

MessageBox.Show(invoiceID.ToString(), "ID");

return invoiceID; //InvoiceTB primary key added
}

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