Export (0) Print
Expand All

HierarchicalDataBoundControlAdapter Class

Customizes the behavior of a HierarchicalDataBoundControl object with which this control adapter is associated, for specific browser requests.

System.Object
  System.Web.UI.Adapters.ControlAdapter
    System.Web.UI.WebControls.Adapters.WebControlAdapter
      System.Web.UI.WebControls.Adapters.HierarchicalDataBoundControlAdapter

Namespace:  System.Web.UI.WebControls.Adapters
Assembly:  System.Web (in System.Web.dll)

public class HierarchicalDataBoundControlAdapter : WebControlAdapter

The HierarchicalDataBoundControlAdapter type exposes the following members.

  NameDescription
Public methodHierarchicalDataBoundControlAdapterInitializes a new instance of the HierarchicalDataBoundControlAdapter class.
Top

  NameDescription
Protected propertyBrowserGets a reference to the browser capabilities of the client making the current HTTP request. (Inherited from ControlAdapter.)
Protected propertyControlRetrieves a strongly typed reference to the HierarchicalDataBoundControl control associated with this HierarchicalDataBoundControlAdapter object.
Protected propertyIsEnabledGets a value indicating whether the Web control and all its parent controls are enabled. (Inherited from WebControlAdapter.)
Protected propertyPageGets a reference to the page where the control associated with this adapter resides. (Inherited from ControlAdapter.)
Protected propertyPageAdapterGets a reference to the page adapter for the page where the associated control resides. (Inherited from ControlAdapter.)
Top

  NameDescription
Protected methodBeginRenderCalled prior to the rendering of a control. In a derived adapter class, generates opening tags that are required by a specific target but not needed by HTML browsers. (Inherited from ControlAdapter.)
Protected methodCreateChildControlsCreates the target-specific child controls for a composite control. (Inherited from ControlAdapter.)
Protected methodEndRenderCalled after the rendering of a control. In a derived adapter class, generates closing tags that are required by a specific target but not needed by HTML browsers. (Inherited from ControlAdapter.)
Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodLoadAdapterControlStateLoads adapter control state information that was saved by SaveAdapterControlState during a previous request to the page where the control associated with this control adapter resides. (Inherited from ControlAdapter.)
Protected methodLoadAdapterViewStateLoads adapter view state information that was saved by SaveAdapterViewState during a previous request to the page where the control associated with this control adapter resides. (Inherited from ControlAdapter.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Protected methodOnInitOverrides the OnInit method for the associated control. (Inherited from ControlAdapter.)
Protected methodOnLoadOverrides the OnLoad method for the associated control. (Inherited from ControlAdapter.)
Protected methodOnPreRenderOverrides the OnPreRender method for the associated control. (Inherited from ControlAdapter.)
Protected methodOnUnloadOverrides the OnUnload method for the associated control. (Inherited from ControlAdapter.)
Protected methodPerformDataBindingBinds the data in the data source of the associated hierarchical data-bound control to the adapter.
Protected methodRenderGenerates the target-specific markup for the control to which the control adapter is attached. (Inherited from WebControlAdapter.)
Protected methodRenderBeginTagCreates the beginning tag for the Web control in the markup that is transmitted to the target browser. (Inherited from WebControlAdapter.)
Protected methodRenderChildrenGenerates the target-specific markup for the child controls in a composite control to which the control adapter is attached. (Inherited from ControlAdapter.)
Protected methodRenderContentsGenerates the target-specific inner markup for the Web control to which the control adapter is attached. (Inherited from WebControlAdapter.)
Protected methodRenderEndTagCreates the ending tag for the Web control in the markup that is transmitted to the target browser. (Inherited from WebControlAdapter.)
Protected methodSaveAdapterControlStateSaves control state information for the control adapter. (Inherited from ControlAdapter.)
Protected methodSaveAdapterViewStateSaves view state information for the control adapter. (Inherited from ControlAdapter.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
Top

The HierarchicalDataBoundControlAdapter class adapts the associated HierarchicalDataBoundControl control to modify the default markup or behavior for a specific browser. You can extend the HierarchicalDataBoundControlAdapter class to further customize rendering of the HierarchicalDataBoundControl control.

A HierarchicalDataBoundControl control is bound to a data source and generates its user interface (or child control hierarchy, typically), by enumerating the items in the data source to which it is bound. For more information on hierarchical data-bound controls, see HierarchicalDataBoundControl.

Control adapters are.NET components that manage one or more stages in the life cycle of a control for a specific browser. Extending the HierarchicalDataBoundControlAdapter class provides access to the life-cycle stages of the HierarchicalDataBoundControl control. For more information, see Architectural Overview of Adaptive Control Behavior.

The initial request for an adapter causes the .NET Framework to search for a mapped adapter for the control, given the characteristics of the requesting browser. Browser definition files are used by the HttpBrowserCapabilities class to identify the characteristics of the client browser and map the adapter to the browser type.

The following code example shows how to extend the HierarchicalDataBoundControlAdapter class to render a hierarchical TreeView control that is bound to an XmlDataSource object.

This code example contains four objects:

  • An adapter derived from the HierarchicalDataBoundControlAdapter class.

  • The .aspx file that incorporates the TreeView control and device-specific content.

  • A browser file to link the adapter to a device type.

  • An XML file that contains a hierarchical list of employees.

This code example consists of four code segments. The first code segment demonstrates how to extend the HierarchicalDataBoundControlAdapter class.

using System;
using System.Web;
using System.Web.UI;
using System.Security.Permissions;

namespace Contoso
{
    [AspNetHostingPermission(
        SecurityAction.Demand, 
        Level = AspNetHostingPermissionLevel.Minimal)]
    [AspNetHostingPermission(
        SecurityAction.InheritanceDemand, 
        Level = AspNetHostingPermissionLevel.Minimal)]
    public class HierarchicalTreeViewAdapter :
        System.Web.UI.WebControls.Adapters.HierarchicalDataBoundControlAdapter
    {
        // Return a strongly-typed TreeView control for adapter. 
        protected new System.Web.UI.WebControls.TreeView Control
        {
            get
            {
                return (System.Web.UI.WebControls.TreeView)base.Control;
            }
        }

        // Verify the DataSourceID property is set prior to binding data. 
        protected override void PerformDataBinding()
        {
            if (Control.DataSourceID != null)
            {
                base.PerformDataBinding();
            }
        }
    }
}

The second code segment demonstrates how to declare a TreeView to bind to an XML data source.

<%@ page language="c#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>HierarchicalDataBoundControl Adapter</title>
</head>
<body>
    <form id="Form1" runat="server">
        <asp:TreeView ID="TreeView1" 
            Runat="server" 
            DataSourceID="XmlDataSource1">

            <DataBindings>
                <asp:TreeNodeBinding    
                    DataMember="employees" Text="Employees"/>
                <asp:TreeNodeBinding    
                    DataMember="employee" TextField="id" />
                <asp:TreeNodeBinding    
                    DataMember="name" TextField="fullname" />
            </DataBindings>
        </asp:TreeView>

        <asp:XmlDataSource ID="XmlDataSource1"  
            Runat="server" 
            DataFile="employees.xml" />
        <br />
    </form>
</body>
</html>

The third code segment shows how to link the TreeView control to the custom adapter for browsers running on Windows CE.

<browsers>
    <browser refID="WinCE">
        <controlAdapters>
            <adapter controlType="System.Web.UI.WebControls.TreeView" 
                adapterType="Contoso.HierarchicalTreeViewAdapter" />
        </controlAdapters>
    </browser>
    <browser refID="IE">
        <controlAdapters>
            <adapter controlType="System.Web.UI.WebControls.TreeView" 
                adapterType="Contoso.HierarchicalTreeViewAdapter" />
        </controlAdapters>
    </browser>
</browsers>

The final code segment provides the XML data that the TreeView control binds to.

.NET Framework

Supported in: 4.6, 4, 3.5, 3.0, 2.0

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Show:
© 2014 Microsoft