SelectionListDesigner.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / MIT / System / Web / UI / MobileControls / Design / SelectionListDesigner.cs / 1305376 / SelectionListDesigner.cs

                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Web.UI.Design.MobileControls 
{ 
    using System;
    using System.Collections; 
    using System.ComponentModel;
    using System.ComponentModel.Design;
    using System.Data;
    using System.Diagnostics; 
    using System.Web.UI.MobileControls;
    using System.Web.UI.Design.MobileControls.Adapters; 
 
    using DataBinding = System.Web.UI.DataBinding;
 
    [
        System.Security.Permissions.SecurityPermission(System.Security.Permissions.SecurityAction.Demand,
        Flags=System.Security.Permissions.SecurityPermissionFlag.UnmanagedCode)
    ] 
    [Obsolete("The System.Web.Mobile.dll assembly has been deprecated and should no longer be used. For information about how to develop ASP.NET mobile applications, see http://go.microsoft.com/fwlink/?LinkId=157231.")]
    internal class SelectionListDesigner : 
        MobileControlDesigner, IListDesigner, IDataSourceProvider 
    {
        private SelectionList           _selectionList; 
        private DesignerVerbCollection  _designerVerbs;

        private DataTable               _dummyDataTable;
        private DataTable               _designTimeDataTable; 

        private const String _dataSourcePropertyName = "DataSource"; 
        private const String _dataMemberPropertyName = "DataMember"; 
        private const String _dataTextFieldPropertyName = "DataTextField";
        private const String _dataValueFieldPropertyName = "DataValueField"; 
        private static readonly Attribute[] _emptyAttrs = new Attribute[0];

        /// 
        ///  
        public String DataValueField
        { 
            get 
            {
                return _selectionList.DataValueField; 
            }
            set
            {
                _selectionList.DataValueField = value; 
            }
        } 
 
        /// 
        ///  
        public String DataTextField
        {
            get
            { 
                return _selectionList.DataTextField;
            } 
            set 
            {
                _selectionList.DataTextField = value; 
            }
        }

        public String DataMember 
        {
            get 
            { 
                return _selectionList.DataMember;
            } 
            set
            {
                _selectionList.DataMember = value;
                OnDataSourceChanged(); 
            }
        } 
 
        public MobileListItemCollection Items
        { 
            get
            {
                return _selectionList.Items;
            } 
        }
 
        ///  
        ///    
        ///       Gets or sets the data source property. 
        ///    
        /// 
        /// 
        ///     
        ///       A string indicating the data source for the designer's control.
        ///     
        ///  
        /// 
        ///     
        ///       Designer implementation of a DataSource property that operates on the
        ///       DataSource property in the control's binding collection.
        ///    
        ///  
        public String DataSource
        { 
            get 
            {
                DataBinding binding = DataBindings[_dataSourcePropertyName]; 

                if (binding != null)
                {
                    return binding.Expression; 
                }
                return String.Empty; 
            } 
            set
            { 
                if ((value == null) || (value.Length == 0))
                {
                    DataBindings.Remove(_dataSourcePropertyName);
                } 
                else
                { 
                    DataBinding binding = DataBindings[_dataSourcePropertyName]; 

                    if (binding == null) 
                    {
                        binding = new DataBinding(_dataSourcePropertyName, typeof(IEnumerable), value);
                    }
                    else 
                    {
                        binding.Expression = value; 
                    } 
                    DataBindings.Add(binding);
                } 

                OnDataSourceChanged();
                OnBindingsCollectionChanged(_dataSourcePropertyName);
            } 
        }
 
        ///  
        ///    
        ///       The designer's collection of verbs. 
        ///    
        /// 
        /// 
        ///     
        ///       An array of type  containing the verbs available to the
        ///       designer. 
        ///     
        /// 
        public override DesignerVerbCollection Verbs 
        {
            get
            {
                if (null == _designerVerbs) 
                {
                    _designerVerbs = base.Verbs; 
                    _designerVerbs.Add(new DesignerVerb(SR.GetString(SR.PropertyBuilderVerb), 
                        new EventHandler(this.OnPropertyBuilder)));
                } 

                return _designerVerbs;
            }
        } 

        ///  
        ///     
        ///       Gets sample data matching the schema of the selected data source.
        ///     
        /// 
        /// 
        ///    The minimum rows of sample data the data source data should contain.
        ///  
        /// 
        ///    Whether the data source being returned is a dummy data source. 
        ///  
        /// 
        ///     
        ///       An IEnumerable containing a live data source for use at
        ///       design time.
        ///    
        ///  
        ///
        protected IEnumerable GetDesignTimeDataSource( 
            int minimumRows, out bool dummyDataSource) 
        {
            IEnumerable selectedDataSource = GetResolvedSelectedDataSource(); 
            return GetDesignTimeDataSource(
                selectedDataSource, minimumRows, out dummyDataSource);
        }
 
        /// 
        ///     
        ///       Gets sample data matching the schema of the selected data source. 
        ///    
        ///  
        /// 
        ///    The selected data source to be used as a reference for the shape of the data.
        /// 
        ///  
        ///    The minimum rows of sample data the data source data should contain.
        ///  
        ///  
        ///    Whether the data source being returned is a dummy data source.
        ///  
        /// 
        ///    
        ///       An IEnumerable containing
        ///       a live data source for use at design time. 
        ///    
        ///  
        /// 
        protected IEnumerable GetDesignTimeDataSource(
            IEnumerable selectedDataSource, int minimumRows, out bool dummyDataSource) 
        {
            DataTable dataTable = _designTimeDataTable;
            dummyDataSource = false;
 
            // use the datatable corresponding to the selected datasource if possible
            if (dataTable == null) 
            { 
                if (selectedDataSource != null)
                { 
                    _designTimeDataTable =
                        DesignTimeData.CreateSampleDataTable(selectedDataSource);
                    dataTable = _designTimeDataTable;
                } 

                if (dataTable == null) 
                { 
                    // fallback on a dummy datasource if we can't create a sample datatable
                    if (_dummyDataTable == null) 
                    {
                        _dummyDataTable = DesignTimeData.CreateDummyDataTable();
                    }
 
                    dataTable = _dummyDataTable;
                    dummyDataSource = true; 
                } 
            }
 
            IEnumerable liveDataSource =
                DesignTimeData.GetDesignTimeDataSource(dataTable, minimumRows);
            return liveDataSource;
        } 

        ///  
        ///     
        ///       Gets the HTML to be used for the design-time representation
        ///       of the control. 
        ///    
        /// 
        /// 
        ///     
        ///       The design-time HTML.
        ///     
        ///  
        protected override String GetDesignTimeNormalHtml()
        { 
            const int numberOfStaticItems = 5;
            IEnumerable selectedDataSource = null;
            String oldDataTextField = null, oldDataValueField = null;
            bool dummyDataSource = false; 

            DesignerTextWriter htmlWriter = new DesignerTextWriter(true); 
 
            MobileListItemCollection items = _selectionList.Items;
            Debug.Assert(items != null, "Items is null in LisControl"); 

            if (items.Count > 0)
            {
                _selectionList.Adapter.Render(htmlWriter); 
            }
            else 
            { 
                MobileListItem[] oldItems = items.GetAll();
                int sampleRows = numberOfStaticItems; 

                // try designtime databinding.
                selectedDataSource = GetResolvedSelectedDataSource();
 
                IEnumerable designTimeDataSource =
                    GetDesignTimeDataSource( 
                    selectedDataSource, 
                    sampleRows,
                    out dummyDataSource); 

                // If dummy datasource is applied, change the data fields so that
                // dummy source will be rendered.
                if (dummyDataSource) 
                {
                    oldDataTextField    = _selectionList.DataTextField; 
                    oldDataValueField   = _selectionList.DataValueField; 
                    _selectionList.DataTextField    = "Column0";
                    _selectionList.DataValueField   = "Column1"; 
                }

                try
                { 
                    _selectionList.DataSource = designTimeDataSource;
                    _selectionList.DataBind(); 
                    _selectionList.Adapter.Render(htmlWriter); 
                }
                finally 
                {
                    _selectionList.DataSource = null;
                    _selectionList.Items.SetAll(oldItems);
 
                    if (dummyDataSource)
                    { 
                        _selectionList.DataTextField = oldDataTextField; 
                        _selectionList.DataValueField = oldDataValueField;
                    } 
                }
            }

            return htmlWriter.ToString(); 
        }
 
        public IEnumerable GetResolvedSelectedDataSource() 
        {
            IEnumerable selectedDataSource = null; 

            DataBinding binding = DataBindings["DataSource"];

            if (binding != null) 
            {
                selectedDataSource = 
                    DesignTimeData.GetSelectedDataSource( 
                    _selectionList,
                    binding.Expression, 
                    DataMember);
            }

            return selectedDataSource; 
        }
 
        ///  
        ///    
        ///       Gets the selected data source component from the component's container. 
        ///    
        /// 
        /// 
        ///     
        ///       An IEnumerable with the
        ///       selected data source, or  if a data source is not found, or if a data 
        ///       source with the same name does not exist. 
        ///    
        ///  
        /// 
        public Object GetSelectedDataSource()
        {
            Object selectedDataSource = null; 

            DataBinding binding = DataBindings[_dataSourcePropertyName]; 
 
            if (binding != null)
            { 
                selectedDataSource =
                    DesignTimeData.GetSelectedDataSource(_selectionList, binding.Expression);
            }
 
            return selectedDataSource;
        } 
 
        /// 
        ///     
        ///       Initializes the designer.
        ///    
        /// 
        ///  
        ///    The control element being designed.
        ///  
        ///  
        ///    
        ///       This is called by the designer host to establish the component being 
        ///       designed.
        ///    
        /// 
        ///  
        public override void Initialize(IComponent component)
        { 
            Debug.Assert(component is System.Web.UI.MobileControls.SelectionList, 
                "SelectionListDesigner.Initialize - Invalid SelectionList Control");
 
            _selectionList = (SelectionList) component;
            base.Initialize(component);
        }
 
        /// 
        ///     
        ///       Invokes the property builder beginning with the specified page. 
        ///    
        ///  
        /// 
        ///    The page to begin with.
        /// 
        protected internal void InvokePropertyBuilder(int initialPage) 
        {
            IComponentChangeService changeService = null; 
            bool result = false; 

            changeService = (IComponentChangeService)GetService(typeof(IComponentChangeService)); 
            if (changeService != null)
            {
                try
                { 
                    changeService.OnComponentChanging(_selectionList, null);
                } 
                catch (CheckoutException ex) 
                {
                    if (ex == CheckoutException.Canceled) 
                    {
                        return;
                    }
                    throw; 
                }
            } 
 
            try
            { 
                SelectionListComponentEditor compEditor = new SelectionListComponentEditor(initialPage);
                result = compEditor.EditComponent(_selectionList);
            }
            finally 
            {
                if (changeService != null) 
                { 
                    changeService.OnComponentChanged(_selectionList, null, null, null);
 
                    if (IMobileWebFormServices != null)
                    {
                        IMobileWebFormServices.ClearUndoStack();
                    } 
                }
            } 
        } 

        ///  
        ///    
        ///       Represents the method that will handle the component change event.
        ///    
        ///  
        /// 
        ///    The source of the event. 
        ///  
        /// 
        ///    The  that provides data about the event. 
        /// 
        public override void OnComponentChanged(Object sender, ComponentChangedEventArgs e)
        {
            if (e.Member != null) 
            {
                if (e.Member.Name.Equals(_dataSourcePropertyName) || 
                    e.Member.Name.Equals(_dataMemberPropertyName)) 
                {
                    OnDataSourceChanged(); 
                }
            }

            base.OnComponentChanged(sender, e); 
        }
 
        ///  
        /// 
        ///     
        ///       Raises the DataSourceChanged event.
        ///    
        /// 
        public void OnDataSourceChanged() 
        {
            _designTimeDataTable = null; 
        } 

        ///  
        ///    
        ///       Represents the method that will handle the property builder event.
        ///    
        ///  
        /// 
        ///    The source of the event. 
        ///  
        /// 
        ///    An EventArgs object that provides data about the event. 
        /// 
        protected void OnPropertyBuilder(Object sender, EventArgs e)
        {
            InvokePropertyBuilder(0); 
        }
 
        ///  
        ///    
        ///       Filter the properties to replace the runtime DataSource property 
        ///       descriptor with the designer's.
        ///    
        /// 
        ///  
        ///    The set of properties to filter.
        ///  
        ///  
        protected override void PreFilterProperties(IDictionary properties)
        { 
            base.PreFilterProperties(properties);

            Type designerType = this.GetType();
 
            DesignerAdapterUtil.AddAttributesToPropertiesOfDifferentType(
                designerType, 
                typeof(String), 
                properties,
                _dataSourcePropertyName, 
                new TypeConverterAttribute(typeof(DataSourceConverter)));

            DesignerAdapterUtil.AddAttributesToProperty(
                designerType, 
                properties,
                _dataMemberPropertyName, 
                _emptyAttrs); 

            DesignerAdapterUtil.AddAttributesToProperty( 
                designerType,
                properties,
                _dataTextFieldPropertyName,
                _emptyAttrs); 

            DesignerAdapterUtil.AddAttributesToProperty( 
                designerType, 
                properties,
                _dataValueFieldPropertyName, 
                _emptyAttrs);
        }
    }
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
//------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Web.UI.Design.MobileControls 
{ 
    using System;
    using System.Collections; 
    using System.ComponentModel;
    using System.ComponentModel.Design;
    using System.Data;
    using System.Diagnostics; 
    using System.Web.UI.MobileControls;
    using System.Web.UI.Design.MobileControls.Adapters; 
 
    using DataBinding = System.Web.UI.DataBinding;
 
    [
        System.Security.Permissions.SecurityPermission(System.Security.Permissions.SecurityAction.Demand,
        Flags=System.Security.Permissions.SecurityPermissionFlag.UnmanagedCode)
    ] 
    [Obsolete("The System.Web.Mobile.dll assembly has been deprecated and should no longer be used. For information about how to develop ASP.NET mobile applications, see http://go.microsoft.com/fwlink/?LinkId=157231.")]
    internal class SelectionListDesigner : 
        MobileControlDesigner, IListDesigner, IDataSourceProvider 
    {
        private SelectionList           _selectionList; 
        private DesignerVerbCollection  _designerVerbs;

        private DataTable               _dummyDataTable;
        private DataTable               _designTimeDataTable; 

        private const String _dataSourcePropertyName = "DataSource"; 
        private const String _dataMemberPropertyName = "DataMember"; 
        private const String _dataTextFieldPropertyName = "DataTextField";
        private const String _dataValueFieldPropertyName = "DataValueField"; 
        private static readonly Attribute[] _emptyAttrs = new Attribute[0];

        /// 
        ///  
        public String DataValueField
        { 
            get 
            {
                return _selectionList.DataValueField; 
            }
            set
            {
                _selectionList.DataValueField = value; 
            }
        } 
 
        /// 
        ///  
        public String DataTextField
        {
            get
            { 
                return _selectionList.DataTextField;
            } 
            set 
            {
                _selectionList.DataTextField = value; 
            }
        }

        public String DataMember 
        {
            get 
            { 
                return _selectionList.DataMember;
            } 
            set
            {
                _selectionList.DataMember = value;
                OnDataSourceChanged(); 
            }
        } 
 
        public MobileListItemCollection Items
        { 
            get
            {
                return _selectionList.Items;
            } 
        }
 
        ///  
        ///    
        ///       Gets or sets the data source property. 
        ///    
        /// 
        /// 
        ///     
        ///       A string indicating the data source for the designer's control.
        ///     
        ///  
        /// 
        ///     
        ///       Designer implementation of a DataSource property that operates on the
        ///       DataSource property in the control's binding collection.
        ///    
        ///  
        public String DataSource
        { 
            get 
            {
                DataBinding binding = DataBindings[_dataSourcePropertyName]; 

                if (binding != null)
                {
                    return binding.Expression; 
                }
                return String.Empty; 
            } 
            set
            { 
                if ((value == null) || (value.Length == 0))
                {
                    DataBindings.Remove(_dataSourcePropertyName);
                } 
                else
                { 
                    DataBinding binding = DataBindings[_dataSourcePropertyName]; 

                    if (binding == null) 
                    {
                        binding = new DataBinding(_dataSourcePropertyName, typeof(IEnumerable), value);
                    }
                    else 
                    {
                        binding.Expression = value; 
                    } 
                    DataBindings.Add(binding);
                } 

                OnDataSourceChanged();
                OnBindingsCollectionChanged(_dataSourcePropertyName);
            } 
        }
 
        ///  
        ///    
        ///       The designer's collection of verbs. 
        ///    
        /// 
        /// 
        ///     
        ///       An array of type  containing the verbs available to the
        ///       designer. 
        ///     
        /// 
        public override DesignerVerbCollection Verbs 
        {
            get
            {
                if (null == _designerVerbs) 
                {
                    _designerVerbs = base.Verbs; 
                    _designerVerbs.Add(new DesignerVerb(SR.GetString(SR.PropertyBuilderVerb), 
                        new EventHandler(this.OnPropertyBuilder)));
                } 

                return _designerVerbs;
            }
        } 

        ///  
        ///     
        ///       Gets sample data matching the schema of the selected data source.
        ///     
        /// 
        /// 
        ///    The minimum rows of sample data the data source data should contain.
        ///  
        /// 
        ///    Whether the data source being returned is a dummy data source. 
        ///  
        /// 
        ///     
        ///       An IEnumerable containing a live data source for use at
        ///       design time.
        ///    
        ///  
        ///
        protected IEnumerable GetDesignTimeDataSource( 
            int minimumRows, out bool dummyDataSource) 
        {
            IEnumerable selectedDataSource = GetResolvedSelectedDataSource(); 
            return GetDesignTimeDataSource(
                selectedDataSource, minimumRows, out dummyDataSource);
        }
 
        /// 
        ///     
        ///       Gets sample data matching the schema of the selected data source. 
        ///    
        ///  
        /// 
        ///    The selected data source to be used as a reference for the shape of the data.
        /// 
        ///  
        ///    The minimum rows of sample data the data source data should contain.
        ///  
        ///  
        ///    Whether the data source being returned is a dummy data source.
        ///  
        /// 
        ///    
        ///       An IEnumerable containing
        ///       a live data source for use at design time. 
        ///    
        ///  
        /// 
        protected IEnumerable GetDesignTimeDataSource(
            IEnumerable selectedDataSource, int minimumRows, out bool dummyDataSource) 
        {
            DataTable dataTable = _designTimeDataTable;
            dummyDataSource = false;
 
            // use the datatable corresponding to the selected datasource if possible
            if (dataTable == null) 
            { 
                if (selectedDataSource != null)
                { 
                    _designTimeDataTable =
                        DesignTimeData.CreateSampleDataTable(selectedDataSource);
                    dataTable = _designTimeDataTable;
                } 

                if (dataTable == null) 
                { 
                    // fallback on a dummy datasource if we can't create a sample datatable
                    if (_dummyDataTable == null) 
                    {
                        _dummyDataTable = DesignTimeData.CreateDummyDataTable();
                    }
 
                    dataTable = _dummyDataTable;
                    dummyDataSource = true; 
                } 
            }
 
            IEnumerable liveDataSource =
                DesignTimeData.GetDesignTimeDataSource(dataTable, minimumRows);
            return liveDataSource;
        } 

        ///  
        ///     
        ///       Gets the HTML to be used for the design-time representation
        ///       of the control. 
        ///    
        /// 
        /// 
        ///     
        ///       The design-time HTML.
        ///     
        ///  
        protected override String GetDesignTimeNormalHtml()
        { 
            const int numberOfStaticItems = 5;
            IEnumerable selectedDataSource = null;
            String oldDataTextField = null, oldDataValueField = null;
            bool dummyDataSource = false; 

            DesignerTextWriter htmlWriter = new DesignerTextWriter(true); 
 
            MobileListItemCollection items = _selectionList.Items;
            Debug.Assert(items != null, "Items is null in LisControl"); 

            if (items.Count > 0)
            {
                _selectionList.Adapter.Render(htmlWriter); 
            }
            else 
            { 
                MobileListItem[] oldItems = items.GetAll();
                int sampleRows = numberOfStaticItems; 

                // try designtime databinding.
                selectedDataSource = GetResolvedSelectedDataSource();
 
                IEnumerable designTimeDataSource =
                    GetDesignTimeDataSource( 
                    selectedDataSource, 
                    sampleRows,
                    out dummyDataSource); 

                // If dummy datasource is applied, change the data fields so that
                // dummy source will be rendered.
                if (dummyDataSource) 
                {
                    oldDataTextField    = _selectionList.DataTextField; 
                    oldDataValueField   = _selectionList.DataValueField; 
                    _selectionList.DataTextField    = "Column0";
                    _selectionList.DataValueField   = "Column1"; 
                }

                try
                { 
                    _selectionList.DataSource = designTimeDataSource;
                    _selectionList.DataBind(); 
                    _selectionList.Adapter.Render(htmlWriter); 
                }
                finally 
                {
                    _selectionList.DataSource = null;
                    _selectionList.Items.SetAll(oldItems);
 
                    if (dummyDataSource)
                    { 
                        _selectionList.DataTextField = oldDataTextField; 
                        _selectionList.DataValueField = oldDataValueField;
                    } 
                }
            }

            return htmlWriter.ToString(); 
        }
 
        public IEnumerable GetResolvedSelectedDataSource() 
        {
            IEnumerable selectedDataSource = null; 

            DataBinding binding = DataBindings["DataSource"];

            if (binding != null) 
            {
                selectedDataSource = 
                    DesignTimeData.GetSelectedDataSource( 
                    _selectionList,
                    binding.Expression, 
                    DataMember);
            }

            return selectedDataSource; 
        }
 
        ///  
        ///    
        ///       Gets the selected data source component from the component's container. 
        ///    
        /// 
        /// 
        ///     
        ///       An IEnumerable with the
        ///       selected data source, or  if a data source is not found, or if a data 
        ///       source with the same name does not exist. 
        ///    
        ///  
        /// 
        public Object GetSelectedDataSource()
        {
            Object selectedDataSource = null; 

            DataBinding binding = DataBindings[_dataSourcePropertyName]; 
 
            if (binding != null)
            { 
                selectedDataSource =
                    DesignTimeData.GetSelectedDataSource(_selectionList, binding.Expression);
            }
 
            return selectedDataSource;
        } 
 
        /// 
        ///     
        ///       Initializes the designer.
        ///    
        /// 
        ///  
        ///    The control element being designed.
        ///  
        ///  
        ///    
        ///       This is called by the designer host to establish the component being 
        ///       designed.
        ///    
        /// 
        ///  
        public override void Initialize(IComponent component)
        { 
            Debug.Assert(component is System.Web.UI.MobileControls.SelectionList, 
                "SelectionListDesigner.Initialize - Invalid SelectionList Control");
 
            _selectionList = (SelectionList) component;
            base.Initialize(component);
        }
 
        /// 
        ///     
        ///       Invokes the property builder beginning with the specified page. 
        ///    
        ///  
        /// 
        ///    The page to begin with.
        /// 
        protected internal void InvokePropertyBuilder(int initialPage) 
        {
            IComponentChangeService changeService = null; 
            bool result = false; 

            changeService = (IComponentChangeService)GetService(typeof(IComponentChangeService)); 
            if (changeService != null)
            {
                try
                { 
                    changeService.OnComponentChanging(_selectionList, null);
                } 
                catch (CheckoutException ex) 
                {
                    if (ex == CheckoutException.Canceled) 
                    {
                        return;
                    }
                    throw; 
                }
            } 
 
            try
            { 
                SelectionListComponentEditor compEditor = new SelectionListComponentEditor(initialPage);
                result = compEditor.EditComponent(_selectionList);
            }
            finally 
            {
                if (changeService != null) 
                { 
                    changeService.OnComponentChanged(_selectionList, null, null, null);
 
                    if (IMobileWebFormServices != null)
                    {
                        IMobileWebFormServices.ClearUndoStack();
                    } 
                }
            } 
        } 

        ///  
        ///    
        ///       Represents the method that will handle the component change event.
        ///    
        ///  
        /// 
        ///    The source of the event. 
        ///  
        /// 
        ///    The  that provides data about the event. 
        /// 
        public override void OnComponentChanged(Object sender, ComponentChangedEventArgs e)
        {
            if (e.Member != null) 
            {
                if (e.Member.Name.Equals(_dataSourcePropertyName) || 
                    e.Member.Name.Equals(_dataMemberPropertyName)) 
                {
                    OnDataSourceChanged(); 
                }
            }

            base.OnComponentChanged(sender, e); 
        }
 
        ///  
        /// 
        ///     
        ///       Raises the DataSourceChanged event.
        ///    
        /// 
        public void OnDataSourceChanged() 
        {
            _designTimeDataTable = null; 
        } 

        ///  
        ///    
        ///       Represents the method that will handle the property builder event.
        ///    
        ///  
        /// 
        ///    The source of the event. 
        ///  
        /// 
        ///    An EventArgs object that provides data about the event. 
        /// 
        protected void OnPropertyBuilder(Object sender, EventArgs e)
        {
            InvokePropertyBuilder(0); 
        }
 
        ///  
        ///    
        ///       Filter the properties to replace the runtime DataSource property 
        ///       descriptor with the designer's.
        ///    
        /// 
        ///  
        ///    The set of properties to filter.
        ///  
        ///  
        protected override void PreFilterProperties(IDictionary properties)
        { 
            base.PreFilterProperties(properties);

            Type designerType = this.GetType();
 
            DesignerAdapterUtil.AddAttributesToPropertiesOfDifferentType(
                designerType, 
                typeof(String), 
                properties,
                _dataSourcePropertyName, 
                new TypeConverterAttribute(typeof(DataSourceConverter)));

            DesignerAdapterUtil.AddAttributesToProperty(
                designerType, 
                properties,
                _dataMemberPropertyName, 
                _emptyAttrs); 

            DesignerAdapterUtil.AddAttributesToProperty( 
                designerType,
                properties,
                _dataTextFieldPropertyName,
                _emptyAttrs); 

            DesignerAdapterUtil.AddAttributesToProperty( 
                designerType, 
                properties,
                _dataValueFieldPropertyName, 
                _emptyAttrs);
        }
    }
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
                        

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