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DetailsViewDesigner Class

Note: This class is new in the .NET Framework version 2.0.

Provides design-time support in a visual designer for the DetailsView control.

Namespace: System.Web.UI.Design.WebControls
Assembly: System.Design (in system.design.dll)

public class DetailsViewDesigner : DataBoundControlDesigner
public class DetailsViewDesigner extends DataBoundControlDesigner
public class DetailsViewDesigner extends DataBoundControlDesigner

In a visual designer, when you switch from Source to Design view, the markup source code that describes the DetailsView control is parsed and a design-time version of the control is created on the design surface. When you switch back to Source view, the design-time control is persisted to markup source code and edited into the markup for the Web page.

The properties of the DetailsViewDesigner class provide the following functionality:

  • The ActionLists property returns a DesignerActionListCollection object, which typically contains an object that is derived from the DesignerActionList class for each level in the inheritance tree of the designer.

  • The AutoFormats property returns a collection of formatting schemes for display in the Auto Format dialog box.

  • The TemplateGroups property returns a collection of template groups for the fields of the associated DetailsView control and the top level DetailsView templates.

  • The UsePreviewControl property always returns true, indicating that the designer creates a temporary copy of the associated DetailsView control to generate the design-time markup.

The DetailsViewDesigner class methods provide the following functionality:

  • The DataBind method binds the associated DetailsView control to a design-time data source.

  • The GetDesignTimeHtml method returns the markup that is used to render the associated DetailsView at design time.

  • The Initialize method prepares the designer to view, edit, and design the associated DetailsView.

  • The OnClick method is called when a region of the design-time view of the associated DetailsView is clicked.

  • The OnSchemaRefreshed method is called when the schema of the data source of the associated DetailsView changes.

  • The PreFilterProperties method is used to remove or add additional properties or to shadow properties of the associated DetailsView.

Design-time editable regions are not supported in the DetailsView control, so the GetEditableDesignerRegionContent and SetEditableDesignerRegionContent methods have no functionality.

The following code example shows how to extend the DetailsViewDesigner class to change the appearance of controls that are derived from the DetailsView control at design time.

The example derives the MyDetailsView control from the DetailsView. The MyDetailsView is simply a copy of the DetailsView control. The example also derives the MyDetailsViewDesigner class from DetailsViewDesigner and places a DesignerAttribute object for MyDetailsViewDesigner on the MyDetailsView control.

The MyDetailsViewDesigner overrides the SampleRowCount property to specify that the pager row of the design-time view of the MyDetailsView contain five page links. It overrides the PreFilterProperties method to make the NamingContainer property visible in the Property grid at design time. It overrides the GetDesignTimeHtml method to include the Caption property, if it is specified, as a new first row in the MyDetailsView grid at design time. If the BorderStyle property of the MyDetailsView is the NotSet or None value, the GetDesignTimeHtml draws a blue dashed border around the control to make its extent more visible.

using System;
using System.Web;
using System.Drawing;
using System.Web.UI.WebControls;
using System.Web.UI.Design.WebControls;
using System.Collections;
using System.ComponentModel;
using System.Security.Permissions;

namespace Examples.CS.WebControls.Design
{
    // The MyDetailsView is a copy of the DetailsView.
    [AspNetHostingPermission(SecurityAction.Demand, 
        Level = AspNetHostingPermissionLevel.Minimal)]
    [AspNetHostingPermission(SecurityAction.InheritanceDemand, 
        Level = AspNetHostingPermissionLevel.Minimal)]
    [Designer(typeof(Examples.CS.WebControls.Design.MyDetailsViewDesigner))]
    public class MyDetailsView : DetailsView
    {
    } // MyDetailsView

    // Override members of the DetailsViewDesigner.
    [ReflectionPermission(SecurityAction.Demand, Flags=ReflectionPermissionFlag.MemberAccess)]
    public class MyDetailsViewDesigner : DetailsViewDesigner
    {
        // Determines the number of page links in the pager row
        // when viewed in the designer.
        protected override int SampleRowCount
        {
            get
            {
                // Render five page links in the pager row.
                return 5;
            }
        } // SampleRowCount

        // Shadow the control properties with design-time properties.
        protected override void PreFilterProperties(IDictionary properties)
        {
            // Call the base method first.
            base.PreFilterProperties(properties);

            // Make the NamingContainer visible in the Properties grid.
            PropertyDescriptor selectProp = 
                (PropertyDescriptor)properties["NamingContainer"];
            properties["NamingContainer"] =
                TypeDescriptor.CreateProperty(selectProp.ComponentType, 
                    selectProp, BrowsableAttribute.Yes);
        } // PreFilterProperties

        // Generate the design-time markup.
        const string capTag = "caption";
        const string trOpen = "tr><td colspan=2 align=center";
        const string trClose = "td></tr";

        public override string GetDesignTimeHtml()
        {
            // Make the full extent of the control more visible in the designer.
            // If the border style is None or NotSet, change the border to
            // a wide, blue, dashed line. Include the caption within the border.
            MyDetailsView myDV = (MyDetailsView)Component;
            string markup = null;
            int charX;

            // Check if the border style should be changed.
            if (myDV.BorderStyle == BorderStyle.NotSet ||
                myDV.BorderStyle == BorderStyle.None)
            {
                BorderStyle oldBorderStyle = myDV.BorderStyle;
                Unit oldBorderWidth = myDV.BorderWidth;
                Color oldBorderColor = myDV.BorderColor;

                // Set design-time properties and catch any exceptions.
                try
                {
                    myDV.BorderStyle = BorderStyle.Dashed;
                    myDV.BorderWidth = Unit.Pixel(3);
                    myDV.BorderColor = Color.Blue;

                    // Call the base method to generate the markup.
                    markup = base.GetDesignTimeHtml();
                }
                catch (Exception ex)
                {
                    markup = GetErrorDesignTimeHtml(ex);
                }
                finally
                {
                    // Restore the properties to their original settings.
                    myDV.BorderStyle = oldBorderStyle;
                    myDV.BorderWidth = oldBorderWidth;
                    myDV.BorderColor = oldBorderColor;
                }
            }
            else
                // Call the base method to generate the markup.
                markup = base.GetDesignTimeHtml();

            // Look for a <caption> tag.
            if ((charX = markup.IndexOf(capTag)) > 0)
            {
                // Replace the first caption with 
                // "tr><td colspan=2 align=center".
                markup = markup.Remove(charX,
                    capTag.Length).Insert(charX, trOpen);

                // Replace the second caption with "td></tr".
                if ((charX = markup.IndexOf(capTag, charX)) > 0)
                    markup = markup.Remove(charX,
                        capTag.Length).Insert(charX, trClose); 
            }
            return markup;

        } // GetDesignTimeHtml
    } // MyDetailsViewDesigner
} // Examples.CS.WebControls.Design

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

Windows 98, Windows 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0
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