While fetching data from the sources like the text file , the xml file or from the database first thing you need to do is to create a data source for it.

Data Source acts like a object of information that holds information about the settings and path that we will use to fetch the data from the selected data source.

Main work of data source :

• Managing connection
• Selecting data
• Managing presentation aspects like paging, caching, etc.
• Manipulating data

The data source controls used for hierarchical data are:

• XMLDataSource - It allows binding to XML files and strings with or without schema information.

• SiteMapDataSource - It allows binding to a provider that supplies site map information.

The SqlDataSource Control

Mainly used while interacting with the Sql Server database and tables associated to it.

<asp:SqlDataSource runat="server" ID="MySqlSource"
   ProviderName='<%$ ConnectionStrings:LocalNWind.ProviderName  %>'
   ConnectionString='<%$ ConnectionStrings:LocalNWind %>'
   SelectionCommand= "SELECT * FROM EMPLOYEES" />

<asp:GridView ID="GridView1" runat="server" DataSourceID="MySqlSource" />

The ObjectDataSource Control

Object data source control is mainly concerned with the data of object kind like the models and entities.

public class Student
{
   public int StudentID { get; set; }
   public string Name { get; set; }
   public string City { get; set; }
   
   public Student()
   { }
   
   public DataSet GetStudents()
   {
      DataSet ds = new DataSet();
      DataTable dt = new DataTable("Students");
      
      dt.Columns.Add("StudentID", typeof(System.Int32));
      dt.Columns.Add("StudentName", typeof(System.String));
      dt.Columns.Add("StudentCity", typeof(System.String));
      dt.Rows.Add(new object[] { 1, "M. H. Kabir", "Calcutta" });
      dt.Rows.Add(new object[] { 2, "Ayan J. Sarkar", "Calcutta" });
      ds.Tables.Add(dt);
      
      return ds;
   }
}