WindowsFormsHelpers.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / DotNET / DotNET / 8.0 / untmp / WIN_WINDOWS / lh_tools_devdiv_wpf / Windows / AccessibleTech / longhorn / Automation / Win32Providers / MS / Internal / AutomationProxies / WindowsFormsHelpers.cs / 1 / WindowsFormsHelpers.cs
                        

                        
                            //---------------------------------------------------------------------------- 
//
// 
//    Copyright (C) Microsoft Corporation.  All rights reserved.
//  
//
// 
// Description: 
//      This proxy is the base class for all proxies that support Windows
//      Forms controls. 
//      All generic Windows Forms functionality goes here.
//
// History:
//  07/01/2003 : a-jeanp Created 
//---------------------------------------------------------------------------
 
using System; 
using System.Text;
using System.Collections; 
using System.Windows.Automation;
using System.Windows.Automation.Provider;
using System.Runtime.InteropServices;
using MS.Win32; 

namespace MS.Internal.AutomationProxies 
{ 
    // Helper static class used by the Win32 proxies to get Winforms information
    static class WindowsFormsHelper 
    {
        #region Proxy Create

        // Static Create method called by UIAutomation to create proxies for Winforms controls. 
        // returns null if unsuccessful
        internal static IRawElementProviderSimple Create(IntPtr hwnd, int idChild, int idObject) 
        { 
            // Currently there is an issue with CLR remoting that causes Accessible.CreateNativeFromEvent() to fail
            // for Winforms controls.  Until that is resolved use AccessibleObjectFromWindow() instead.  It will 
            // return a Native IAccessble and not a OleAcc implementaion.  Winforms does provide a Native IAccessible.

            Accessible acc = null;
            if (Accessible.AccessibleObjectFromWindow(hwnd, idObject, ref acc) != NativeMethods.S_OK || acc == null) 
            {
                return null; 
            } 

            switch (acc.Role) 
            {
                // ===========================================================
                // WinformsSpinner controls are not identifiable by classname or
                // other simple properties.  The following case calls the 
                // WinformsSpinner constructor which in turn tries to establish
                // the class of the control as a fact or returns null. 
                case AccessibleRole.Combobox: 
                    return WinformsSpinner.Create( hwnd, idChild, idObject );
                // =========================================================== 

                case AccessibleRole.SpinButton:
                    return WindowsUpDown.Create( hwnd, idChild, idObject );
 
                case AccessibleRole.Grouping:
                    return new WindowsButton(hwnd, null, WindowsButton.ButtonType.GroupBox, Misc.GetWindowStyle(hwnd) & NativeMethods.BS_TYPEMASK, acc); 
 
                case AccessibleRole.StatusBar:
                    WindowsStatusBar sb = new WindowsStatusBar(hwnd, null, 0, acc); 
                    if (sb == null)
                    {
                        return null;
                    } 
                    return idChild == NativeMethods.CHILD_SELF ? sb : sb.CreateStatusBarPane(idChild);
 
                default: 
                    break;
            } 

            return null;
        }
 
        // Static Create method called by UIAutomation to create a Button proxy for Winforms Buttons.
        // returns null if unsuccessful 
        internal static IRawElementProviderSimple CreateButton(IntPtr hwnd) 
        {
            // Currently there is an issue with CLR remoting that causes Accessible.CreateNativeFromEvent() to fail 
            // for Winforms controls.  Until that is resolved use AccessibleObjectFromWindow() instead.  It will
            // return a Native IAccessble and not a OleAcc implementaion.  Winforms does provide a Native IAccessible.

            Accessible acc = null; 
            if (Accessible.AccessibleObjectFromWindow(hwnd, NativeMethods.OBJID_CLIENT, ref acc) != NativeMethods.S_OK || acc == null)
            { 
                return null; 
            }
 
            switch (acc.Role)
            {
                case AccessibleRole.CheckButton:
                    return new WindowsButton(hwnd, null, WindowsButton.ButtonType.CheckBox, Misc.GetWindowStyle(hwnd) & NativeMethods.BS_TYPEMASK, acc); 

                case AccessibleRole.Grouping: 
                    return new WindowsButton(hwnd, null, WindowsButton.ButtonType.GroupBox, Misc.GetWindowStyle(hwnd) & NativeMethods.BS_TYPEMASK, acc); 

                case AccessibleRole.PushButton: 
                    return new WindowsButton(hwnd, null, WindowsButton.ButtonType.PushButton, Misc.GetWindowStyle(hwnd) & NativeMethods.BS_TYPEMASK, acc);

                case AccessibleRole.RadioButton:
                    return new WindowsButton(hwnd, null, WindowsButton.ButtonType.RadioButton, Misc.GetWindowStyle(hwnd) & NativeMethods.BS_TYPEMASK, acc); 

                default: 
                    break; 
            }
 
            return null;
        }

        #endregion 

        #region Internal Methods 
 
        // ------------------------------------------------------
        // 
        // Internal Methods
        //
        // -----------------------------------------------------
 
        // Checks if an hwnd is a winform.
        // Returns True/False if the hwnd is a winform. 
        static internal FormControlState GetControlState(IntPtr hwnd) 
        {
            return IsWindowsFormsControl(hwnd) ? FormControlState.True : FormControlState.False; 
        }

        // Checks if an a class name is a winform classname.
        // Returns True/False if the classname is a winform. 
        static internal bool IsWindowsFormsControl(string className)
        { 
            return className.IndexOf(_WindowsFormsClassName, StringComparison.OrdinalIgnoreCase) > -1; 
        }
 
        // Checks if an a class name is a winform classname.
        // Returns True/False if the classname is a winform.
        static internal bool IsWindowsFormsControl(IntPtr hwnd)
        { 
            return IsWindowsFormsControl(Misc.GetClassName(hwnd));
        } 
 
        static internal bool IsWindowsFormsControl(IntPtr hwnd, ref FormControlState state)
        { 
            if (state == FormControlState.Undeterminate)
            {
                state = GetControlState(hwnd);
            } 

            return state == FormControlState.True ? true : false; 
        } 

        // The control name is the only real "Persistent" ID in Windows Forms 
        static internal string WindowsFormsID(IntPtr hwnd)
        {
            return GetControlName(hwnd);
        } 

        // Extract the internal Name property of the Windows Forms control using 
        // the WM_GETCONTROLNAME message. 
        static internal string GetControlName(IntPtr hwnd)
        { 
            string winFormsID = "";
            if (XSendMessage.XSend(hwnd, WM_GETCONTROLNAME, new IntPtr(Misc.MaxLengthNameProperty), ref winFormsID, Misc.MaxLengthNameProperty))
            {
                return winFormsID; 
            }
            return null; 
        } 

        #endregion 

        #region Internal Fields

        // ------------------------------------------------------ 
        //
        // Internal Fields 
        // 
        // ------------------------------------------------------
 
        // The different states for figurating out if an hwnd is a winform.
        // Underminate implies value not set yet. Must call GetControlState,
        // otherwise the state is cached.
        internal enum FormControlState 
        {
            Undeterminate, 
            False, 
            True,
        } 

        #endregion

        #region Private Fields 

        // ----------------------------------------------------- 
        // 
        // Private Fields
        // 
        // ------------------------------------------------------

        // Use this string to determine if this is a Windows Forms control or not
        private const string _WindowsFormsClassName = "windowsforms"; 

        // Private Message to know the underlying name for a control 
        private static int WM_GETCONTROLNAME = Misc.RegisterWindowMessage("WM_GETCONTROLNAME"); 

        #endregion 
    }
}

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

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