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DataBinder Class

Definition

Provides support for rapid application development (RAD) designers to generate and parse data-binding expression syntax. This class cannot be inherited.

public ref class DataBinder sealed
public sealed class DataBinder
type DataBinder = class
Public NotInheritable Class DataBinder
Inheritance
DataBinder

Examples

The following example uses the static GetPropertyValue method to populate the fields of a Repeater control using an ArrayList of Product objects. The Eval method could be applied with the same syntax, but it would not perform as quickly.

This example uses a custom Product class which exposes a string Model property and a numeric UnitPrice property.

<%@ Page Language="C#" %>
<%@ Import Namespace="ASPSample" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
protected void  Page_Load(object sender, EventArgs e)
{
        // Create and populate an ArrayList to store the products.
        ArrayList ProductList = new ArrayList();
        ProductList.Add(new Product("Standard", 99.95));
        ProductList.Add(new Product("Deluxe", 159.95));

        // Bind the array list to Repeater
        ListRepeater.DataSource = ProductList;
        ListRepeater.DataBind();
}
</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title>DataBinder Example</title>
</head>
<body>
<form id="Form2" runat="server">
<table>
<asp:Repeater id="ListRepeater" runat="server">
    <HeaderTemplate>
    <tr>
        <th style="width:50; text-align:left">Model</th>
        <th style="width:100; text-align:right">Unit Price</th>
    </tr>
    </HeaderTemplate>
    <ItemTemplate>
    <tr>
        <!-- Databind to the Product information using the DataBinder methods. 
             The Container.DataItem refers to the ArrayList object bound to 
             the ASP:Repeater in the Page Load event. -->
        <td>
            <%#DataBinder.GetPropertyValue(Container.DataItem, "Model")%>
        </td>
        <!-- Format the UnitPrice as currency. ({0:c}) -->
        <td style="text-align:right">
            <%#DataBinder.GetPropertyValue(Container.DataItem,
                         "UnitPrice", "{0:c}")%>
        </td>
    </tr>
    </ItemTemplate>
</asp:Repeater>
</table>
</form>
</body>
</html>
<%@ Page Language="vb" %>
<%@ Import Namespace="ASPSample" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
    Private Sub Page_Load(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles MyBase.Load

        ' Create and populate an ArrayList to store the products.
        Dim ProductList As New ArrayList
        ProductList.Add(New Product("Standard", 99.95))
        ProductList.Add(New Product("Deluxe", 159.95))

        ' Bind the array list to Repeater
        ListRepeater.DataSource = ProductList
        ListRepeater.DataBind()

    End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title>DataBinder Example</title>
</head>
<body>
<form id="Form2" runat="server">
<table>
<asp:Repeater id="ListRepeater" runat="server">
    <HeaderTemplate>
    <tr>
        <th style="width:50; text-align:left">Model</th>
        <th style="width:100; text-align:right">Unit Price</th>
    </tr>
    </HeaderTemplate>
    <ItemTemplate>
    <tr>
        <!-- Databind to the Product information using the DataBinder methods. 
             The Container.DataItem refers to the ArrayList object bound to 
             the ASP:Repeater in the Page Load event. -->
        <td>
            <%#DataBinder.GetPropertyValue(Container.DataItem, "Model")%>
        </td>
        <!-- Format the UnitPrice as currency. ({0:c}) -->
        <td style="text-align:right">
            <%#DataBinder.GetPropertyValue(Container.DataItem, _
                         "UnitPrice", "{0:c}")%>
        </td>
    </tr>
    </ItemTemplate>
</asp:Repeater>
</table>
</form>
</body>
</html>

The following code is the custom Product class. This code should be included in a separate class file in the App_Code directory, such as Product.cs or Product.vb.

namespace ASPSample
{

    public class Product
    {
        string _Model;
        double _UnitPrice;

        public Product(string Model, double UnitPrice)
        {
            _Model = Model;
            _UnitPrice = UnitPrice;
        }

        // The product Model.
        public string Model
        {
            get {return _Model;}
            set {_Model = value;}
        }
            
        // The price of the each product.
        public double UnitPrice
        {
            get {return _UnitPrice;}
            set {_UnitPrice = value;}
        }
    }
}
Namespace ASPSample

    Public Class Product
        Private _Model As String
        Private _UnitPrice As Double

        ' The product Model.
        Public Property Model() As String
            Get
                Return _Model
            End Get
            Set(ByVal Value As String)
                _Model = Value
            End Set
        End Property

        ' The price of the each product.
        Public Property UnitPrice() As Double
            Get
                Return _UnitPrice
            End Get
            Set(ByVal Value As Double)
                _UnitPrice = Value
            End Set
        End Property


        Public Sub New(ByVal Model As String, ByVal UnitPrice As Double)
            _Model = Model
            _UnitPrice = UnitPrice
        End Sub

    End Class

End Namespace

Remarks

You can use the overloaded static Eval method of this class in data-binding syntax in an ASP.NET Web page. This provides an easier syntax to work with than standard data binding. However, because DataBinder.Eval provides automatic type conversion, it can result in slower performance.

For more information about ASP.NET data binding, expressions, and syntax, see Binding to Databases and Data-Binding Expressions Overview.

Starting in .NET Framework 4.5, you can use model binding to simplify some of the tasks that you had to perform through data-binding in earlier versions. For a tutorial series on using model binding with Web Forms, see Model Binding and Web Forms.

Constructors

DataBinder()

Initializes a new instance of the DataBinder class.

Properties

EnableCaching

Gets or sets a value that indicates whether data caching is enabled at run time.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
Eval(Object, String, String)

Evaluates data-binding expressions at run time and formats the result as a string.

Eval(Object, String)

Evaluates data-binding expressions at run time.

GetDataItem(Object, Boolean)

Retrieves an object's declared data item, indicating success or failure.

GetDataItem(Object)

Retrieves an object's declared data item.

GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetIndexedPropertyValue(Object, String, String)

Retrieves the value of the specified property for the specified container, and then formats the results.

GetIndexedPropertyValue(Object, String)

Retrieves the value of a property of the specified container and navigation path.

GetPropertyValue(Object, String, String)

Retrieves the value of the specified property of the specified object, and then formats the results.

GetPropertyValue(Object, String)

Retrieves the value of the specified property of the specified object.

GetType()

Gets the Type of the current instance.

(Inherited from Object)
IsBindableType(Type)

Determines whether the specified data type can be bound.

MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also