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GridView.DataBind Method

Definition

Binds the data source to the GridView control. This method cannot be inherited.

public:
 override void DataBind();
public override sealed void DataBind ();
override this.DataBind : unit -> unit
Public Overrides NotOverridable Sub DataBind ()

Examples

The following example demonstrates how to use the DataBind() method to bind a data source to a GridView control.


<%@ Page language="C#" %>
<%@ import namespace="System.Data" %>
<%@ import namespace="System.Data.SqlClient" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  void Page_Load(Object sender, EventArgs e)
  {
    
    // This example uses Microsoft SQL Server and connects
    // to the Northwind sample database. The data source needs
    // to be bound to the GridView control only when the 
    // page is first loaded. Thereafter, the values are
    // stored in view state.                      
    if(!IsPostBack)
    {
        
      // Declare the query string.
      String queryString = 
        "Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]";
        
      // Run the query and bind the resulting DataSet
      // to the GridView control.
      DataSet ds = GetData(queryString);
      if (ds.Tables.Count > 0)
      {
        AuthorsGridView.DataSource = ds;
        AuthorsGridView.DataBind();
      }
      else
      {
        Message.Text = "Unable to connect to the database.";
      }
            
    }     
    
  }
    
  DataSet GetData(String queryString)
  {

    // Retrieve the connection string stored in the Web.config file.
    String connectionString = ConfigurationManager.ConnectionStrings["NorthWindConnectionString"].ConnectionString;      
 
    DataSet ds = new DataSet();
        
    try
    {
      // Connect to the database and run the query.
      SqlConnection connection = new SqlConnection(connectionString);        
      SqlDataAdapter adapter = new SqlDataAdapter(queryString, connection);
        
      // Fill the DataSet.
      adapter.Fill(ds);
            
    }
    catch(Exception ex)
    {
        
      // The connection failed. Display an error message.
      Message.Text = "Unable to connect to the database.";
        
    }
        
    return ds;
        
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView DataBind Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView DataBind Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
               
      <br/>    

      <asp:gridview id="AuthorsGridView" 
        autogeneratecolumns="true" 
        runat="server">
      </asp:gridview>
                        
    </form>
  </body>
</html>

<%@ Page language="VB" %>
<%@ import namespace="System.Data" %>
<%@ import namespace="System.Data.SqlClient" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

  Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
    
    ' This example uses Microsoft SQL Server and connects
    ' to the Northwind sample database. The data source needs
    ' to be bound to the GridView control only when the 
    ' page is first loaded. Thereafter, the values are
    ' stored in view state.                      
    If Not IsPostBack Then
        
      ' Declare the query string.
      Dim queryString As String = _
        "Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        
      ' Run the query and bind the resulting DataSet
      ' to the GridView control.
      Dim ds As DataSet = GetData(queryString)
      If (ds.Tables.Count > 0) Then
      
        AuthorsGridView.DataSource = ds
        AuthorsGridView.DataBind()
      
      Else
      
        Message.Text = "Unable to connect to the database."
        
      End If
            
    End If
    
  End Sub
    
  Function GetData(ByVal queryString As String) As DataSet
    
    ' Retrieve the connection string stored in the Web.config file.
    Dim connectionString As String = ConfigurationManager.ConnectionStrings("NorthWindConnectionString").ConnectionString
 
    Dim ds As New DataSet()
        
    Try

      ' Connect to the database and run the query.
      Dim connection As New SqlConnection(connectionString)
      Dim adapter As New SqlDataAdapter(queryString, Connection)
        
      ' Fill the DataSet.
      Adapter.Fill(ds)
            
    
    Catch ex As Exception
        
      ' The connection failed. Display an error message.
      Message.Text = "Unable to connect to the database."
        
    End Try
        
    Return ds
        
  End Function
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView DataBind Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView DataBind Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
               
      <br/>    

      <asp:gridview id="AuthorsGridView" 
        autogeneratecolumns="true" 
        runat="server">
      </asp:gridview>
                        
    </form>
  </body>
</html>

Remarks

Use the DataBind() method to bind data from a data source to the GridView control. This method resolves all data-binding expressions in the active template of the control.

The DataBind method is called automatically if the DataSourceID property of the GridView control refers to a valid data source control.

Instead of manually calling the DataBind method, you can use model binding with your DataBind control by setting the SelectMethod property to the name of a method that returns data for the GridView. The GridView is then automatically populated with the data that is returned from the select method. Model binding can simplify your code for working with data. For more information, see Model Binding and Web Forms.

Applies to

See also