Access database data from the code behind using ASP.NET C#

Question

I am developing a web template with ASP.NET using C#. My connection string is:

<connectionStrings>
<add name="NorthwindConnectionString" 
connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\SecurityTutorials.mdf;Integrated Security=True;User Instance=True" 
providerName="System.Data.SqlClient"/>
</connectionStrings>

and the access of the connection string is as below:

string connStr = ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ConnectionString;

my SqlDataSource is as follows:

 <asp:SqlDataSource ID="SqlDataSource1" runat="server" 
 ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>" 
 SelectCommand="SELECT [ProductID], [ProductName], [Discontinued] FROM [Alphabetical list of products]"
 InsertCommand = "INSERT INTO [Alphabetical list of products] (ProductID, ProductName, Discontinued)VALUES(@ProductID,@ProductName,@Discontinued)">
<InsertParameters>
<asp:Parameter Name="ProductID" Type="String" />
<asp:Parameter Name="ProductName" Type="String" />
<asp:Parameter Name="Discontinued" Type="String" />
</InsertParameters> 
</asp:SqlDataSource>

I have put a ListView on the page to display the data. Now how can I access the data in the database and how can I retrieve the data and show it inside the page using code behind?

As you know by using <%# Eval("ProductName") %> inside the page all data are accessible. For example, I have a column ProductName , I want to get the data in this column, do some reformatting and pass it to the page form code behind, and also write the SqlDataSource at the code behind.

Answer 1

I bet there are more options than this one, but this is how I would've done it. Cut out the SqlDataSource in the page and fetch and bind the data from the code:

using (var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ConnectionString)
{
  var selectCommand = new SqlCommand("SELECT ...");

  selectCommand.CommandType = CommandType.Text;
  selectCommand.Connection = connection;

  var dataAdapter = new SqlDataAdapter()
  dataAdapter.SelectCommand = selectCommand

  var dataSet = new DataSet();

  connection.Open()
  dataAdapter.Fill(dataSet, "myDataSet");
  connection.Close()

  // now, the dataSet.Tables[0] is a DataTable with your data in it. You can add, edit or remove data in this table before binding it to the ListView

  myListView.DataSource = dataSet;
  myListView.DataBind();
}

In this example, you'll have to write separate code for insertion of data. If dealing with ASP.NET, I write my code like this on purpose, since ASP.NET applications are stateless and thus don't remember any state or data (other than what's stored in Session or ViewState)

Answer 2

As an alternative, you could hook onto the ItemDataBound event of the ListView. See the example code in the MSDN Library: http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.listview.itemdatabound.aspx