ItemContainerPattern.cs source code in C# .NET

                        Code:
                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / UIAutomation / UIAutomationClient / System / Windows / Automation / ItemContainerPattern.cs / 1305600 / ItemContainerPattern.cs
                        
                        
                            //---------------------------------------------------------------------------- 
//
// 
//    Copyright (C) Microsoft Corporation.  All rights reserved.
//  
//
// 
// Description: Client-side wrapper for ItemContainer Pattern 
//
// History: 
//  10/22/2008 : [....] - created
//
//---------------------------------------------------------------------------
 
using System;
using System.Windows.Automation.Provider; 
using MS.Internal.Automation; 
using System.Runtime.InteropServices;
using System.Globalization; 

namespace System.Windows.Automation
{
    ///  
    /// Represents Containers that maintains items and support item look up by propety value.
    ///  
#if (INTERNAL_COMPILE) 
    internal class ItemContainerPattern: BasePattern
#else 
    public class ItemContainerPattern: BasePattern
#endif
    {
        //----------------------------------------------------- 
        //
        //  Constructors 
        // 
        //-----------------------------------------------------
 
        #region Constructors

        private ItemContainerPattern(AutomationElement el, SafePatternHandle hPattern)
            : base(el, hPattern) 
        {
            _hPattern = hPattern; 
        } 

        #endregion Constructors 


        //------------------------------------------------------
        // 
        //  Public Constants / Readonly Fields
        // 
        //----------------------------------------------------- 

        #region Public Constants and Readonly Fields 

        /// ItemContainer pattern
        public static readonly AutomationPattern Pattern = ItemContainerPatternIdentifiers.Pattern;
 
        #endregion Public Constants and Readonly Fields
 
 
        //------------------------------------------------------
        // 
        //  Public Methods
        //
        //------------------------------------------------------
 
        #region Public Methods
 
        ///  
        /// Find item by specified property/value. It will return
        /// placeholder which depending upon it's virtualization state may 
        /// or may not have the information of the complete peer/Wrapper.
        ///
        /// Throws ArgumentException if the property requested is not one that the
        /// container supports searching over. Supports Name property, AutomationId, 
        /// IsSelected and ControlType.
        /// 
        /// This method is expected to be relatively slow, since it may need to 
        /// traverse multiple objects in order to find a matching one.
        /// When used in a loop to return multiple items, no specific order is 
        /// defined so long as each item is returned only once (ie. loop should
        /// terminate). This method is also item-centric, not UI-centric, so items
        /// with multiple UI representations need only be returned once.
        /// 
        /// A special propertyId of 0 means ‘match all items’. This can be used
        /// with startAfter=NULL to get the first item, and then to get successive 
        /// items. 
        /// 
        /// this represents the item after which the container wants to begin search 
        /// corresponds to property for whose value it want to search over.
        /// value to be searched for, for specified property
        /// The first item which matches the searched criterion, if no item matches, it returns null  
        public AutomationElement FindItemByProperty(AutomationElement startAfter, AutomationProperty property, object value) 
        {
           SafeNodeHandle hNode; 
 
           // Invalidate the "value" passed against the "property" before passing it to UIACore, Don't invalidate if search is being done for "null" property
           // FindItemByProperty supports find for null property. 
           if (property != null)
           {
               value = PropertyValueValidateAndMap(property, value);
           } 

           if (startAfter != null) 
           { 
               if (property != null)
                   hNode = UiaCoreApi.ItemContainerPattern_FindItemByProperty(_hPattern, startAfter.RawNode, property.Id, value); 
               else
                   hNode = UiaCoreApi.ItemContainerPattern_FindItemByProperty(_hPattern, startAfter.RawNode, 0, null);
           }
           else 
           {
               if (property != null) 
                   hNode = UiaCoreApi.ItemContainerPattern_FindItemByProperty(_hPattern, new SafeNodeHandle(), property.Id, value); 
               else
                   hNode = UiaCoreApi.ItemContainerPattern_FindItemByProperty(_hPattern, new SafeNodeHandle(), 0, null); 
           }


           AutomationElement wrappedElement = AutomationElement.Wrap(hNode); 
           return wrappedElement;
        } 
 
        #endregion Public Methods
 
       //-----------------------------------------------------
       //
       //  Private Methods
       // 
       //------------------------------------------------------
 
       #region Private Methods 

        private object PropertyValueValidateAndMap(AutomationProperty property, object value) 
        {
            AutomationPropertyInfo info;
            if (!Schema.GetPropertyInfo(property, out info))
            { 
                throw new ArgumentException(SR.Get(SRID.UnsupportedProperty));
            } 
 
            // Check type is appropriate: NotSupported is allowed against any property,
            // null is allowed for any reference type (ie not for value types), otherwise 
            // type must be assignable from expected type.
            Type expectedType = info.Type;
            if (value != AutomationElement.NotSupported &&
                ((value == null && expectedType.IsValueType) 
                || (value != null && !expectedType.IsAssignableFrom(value.GetType()))))
            { 
                throw new ArgumentException(SR.Get(SRID.PropertyConditionIncorrectType, property.ProgrammaticName, expectedType.Name)); 
            }
 
            // Some types are handled differently in managed vs unmanaged - handle those here...
            if (value is AutomationElement)
            {
                // If this is a comparison against a Raw/LogicalElement, 
                // save the runtime ID instead of the element so that we
                // can take it cross-proc if needed. 
                value = ((AutomationElement)value).GetRuntimeId(); 
            }
            else if (value is ControlType) 
            {
                // If this is a control type, use the ID, not the CLR object
                value = ((ControlType)value).Id;
            } 
            else if (value is Rect)
            { 
                Rect rc = (Rect)value; 
                value = new double[] { rc.Left, rc.Top, rc.Width, rc.Height };
            } 
            else if (value is Point)
            {
                Point pt = (Point)value;
                value = new double[] { pt.X, pt.Y }; 
            }
            else if (value is CultureInfo) 
            { 
                value = ((CultureInfo)value).LCID;
            } 

            return value;
        }
 
        #endregion Internal Methods
 
        //----------------------------------------------------- 
        //
        //  Internal Methods 
        //
        //-----------------------------------------------------

        #region Internal Methods 

        static internal object Wrap(AutomationElement el, SafePatternHandle hPattern, bool cached) 
        { 
            return new ItemContainerPattern(el, hPattern);
        } 

        #endregion Internal Methods

        //----------------------------------------------------- 
        //
        //  Private Fields 
        // 
        //------------------------------------------------------
 
        #region Private Fields

        private SafePatternHandle _hPattern;
 
        #endregion Private Fields
 
    } 
}
 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
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ItemContainerPattern.cs source code in C# .NET

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