How to create a simple Master-Slave DataGrid

Introduction

In this article, I will provide code sample on how to make a simple Master-Slave DataGrid. First, add a DataGrid on the page and make a "Select" column using property builder.

Master-Slave DataGrid in C# Code

private void Page_Load(object sender, System.EventArgs e)
{
  if(!Page.IsPostBack) 
  { 
    // Binds the DataGrid
    BindGrid(); 

    }
  } 
  public void BindGrid() 
  { 
    SqlCommand myCommand = 
        new SqlCommand("SELECT * FROM Categories",myConnection); 
    myCommand.CommandType = CommandType.Text; 
    try 
    { 
      // Opens database connection
      myConnection.Open(); 
      // Execute SqlCommand that returns datareader
      SqlDataReader dr = 
          myCommand.ExecuteReader(CommandBehavior.CloseConnection);
      // Populate MasterGrid
      MasterGrid.DataSource = dr; 
      // Binds MasterGrid to the page
      MasterGrid.DataBind(); 

    } 

    // Catch SqlException 
    catch ( SqlException SqlEx ) 
    { 
      // TODO
    }
    // Catch general Exception
    catch ( Exception ex ) 
    {
      // TODO
    }
    // Closes the database connection
    finally { myConnection.Close(); } 
  }

  // This event is fired when the Selection is made in MasterDataGrid
  private void ViewSelectionDetails(object sender, System.EventArgs e)
  {
    // Gets the primary key value from the Master DataGrid
    Int32 categoryID = 
         Convert.ToInt32(MasterGrid.SelectedItem.Cells[0].Text); 
    Label2.Text = categoryID.ToString();
    // Sends the key to the Slave DataGrid
    PopulateSlaveGrid( categoryID );

  }
  // This method populates Slave DataGrid
  public void PopulateSlaveGrid(Int32 cID) 
  { 
    // SQL QUERY to view the selected Item details
    string commandString = 
      "SELECT CategoryName,Description FROM Categories WHERE CategoryID="+cID; 

    // Make an instance of SqlDataAdapter and Assign it the query string
    SqlDataAdapter ad = new SqlDataAdapter(commandString,myConnection); 
    // DataSet instance created
    DataSet ds = new DataSet(); 
    // Fill DataSet 
    ad.Fill(ds,"Categories"); 
    try 
    { 
      // Opens database connection
      myConnection.Open(); 
      // Populate SlaveGrid
      SlaveGrid.DataSource = ds; 
      // Binds SlaveGrid to the page
      SlaveGrid.DataBind(); 
    } 

    // Catch SqlException 
    catch ( SqlException SqlEx ) 
    { 
      // TODO
    }
    // Catch general Exception
    catch ( Exception ex ) 
    {
      // TODO
    }
    // Closes the database connection
    finally { myConnection.Close(); } 
  } 
}

This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves. If in doubt please contact the author via the discussion board below.

A list of licenses authors might use can be found here