ADO.NET 3.5 Cookbook, 2nd Edition

9.1. Using an XML File to Save and Load a DataSet or a DataTable

Problem

You need to save a DataSet or DataTable as an XML file and create a DataSet or DataTable from an XML file.

Solution

Use the XmlTextWriter and XmlTextReader classes together with the WriteXml() and ReadXml() methods of the DataSet and DataTable classes.

The solution creates a DataSet containing a subset of data from the Person.Contact table in AdventureWorks. The XML schema and data for the DataSet is written to a file named ContactDataset.xml. Next, the solution creates a DataSet and reads in schema and data from the XML file ContactDataSet.xml. Finally, the contents of the DataSet are written to the console.

The C# code in Program.cs in the project SaveLoadDataSetXml is shown in Example 9-1.

Example 9-1. File: Program.cs for SaveLoadDataSetXml solution

using System; using System.Data; using System.Data.SqlClient; using System.IO; using System.Xml; using System.Text; namespace SaveLoadDataSetXml { class Program { private const string fileName = @"..\..\..\ContactDataSet.xml"; static void Main(string[] args) { string sqlConnectString = "Data Source=(local);" + "Integrated security=SSPI;Initial Catalog=AdventureWorks;"; string sqlSelect = "SELECT ContactID, FirstName, LastName " + "FROM Person.Contact WHERE ContactID BETWEEN 10 AND 13"; // Fill the DataSet using a DataAdapter DataSet dsSource = new DataSet("ContactDataSet"); SqlDataAdapter da = new SqlDataAdapter(sqlSelect, sqlConnectString); da.TableMappings.Add("Table", ...