COM2AboutBoxPropertyDescriptor.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / WinForms / Managed / System / WinForms / ComponentModel / COM2Interop / COM2AboutBoxPropertyDescriptor.cs / 1305376 / COM2AboutBoxPropertyDescriptor.cs
                        

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

namespace System.Windows.Forms.ComponentModel.Com2Interop { 
    using System.Runtime.Serialization.Formatters; 
    using System.Runtime.InteropServices;
    using System.ComponentModel; 
    using System.Diagnostics;
    using System.Diagnostics.CodeAnalysis;
    using System;
    using System.ComponentModel.Design; 
    using Microsoft.Win32;
    using System.Collections; 
    using System.Drawing.Design; 

    internal class Com2AboutBoxPropertyDescriptor : Com2PropertyDescriptor { 
        private TypeConverter converter;
        private UITypeEditor  editor;

        public Com2AboutBoxPropertyDescriptor() : base(NativeMethods.ActiveX.DISPID_ABOUTBOX, "About", new Attribute[]{new DispIdAttribute(NativeMethods.ActiveX.DISPID_ABOUTBOX), 
                                                                                      DesignerSerializationVisibilityAttribute.Hidden,
                                                                                      new DescriptionAttribute(SR.GetString(SR.AboutBoxDesc)), 
                                                                                      new ParenthesizePropertyNameAttribute(true)}, true, typeof(string), null, false) { 
        }
 
        /// 
        /// 
        ///     Retrieves the type of the component this PropertyDescriptor is bound to.
        ///  
        public override Type ComponentType {
            get { 
               return typeof(UnsafeNativeMethods.IDispatch); 
            }
        } 


        /// 
        ///  
        ///      Retrieves the type converter for this property.
        ///  
        public override TypeConverter Converter { 
            get {
                if (converter == null) { 
                    converter = new TypeConverter();
                }
                return converter;
            } 
        }
        ///  
        ///  
        ///     Indicates whether this property is read only.
        ///  
        public override bool IsReadOnly {
            get {
               return true;
            } 
        }
 
        ///  
        /// 
        ///     Retrieves the type of the property. 
        /// 
        public override Type PropertyType {
            get {
               return typeof(string); 
            }
        } 
 
        /// 
        ///  
        ///     Indicates whether reset will change the value of the component.  If there
        ///     is a DefaultValueAttribute, then this will return true if getValue returns
        ///     something different than the default value.  If there is a reset method and
        ///     a shouldPersist method, this will return what shouldPersist returns. 
        ///     If there is just a reset method, this always returns true.  If none of these
        ///     cases apply, this returns false. 
        ///  
        public override bool CanResetValue(object component) {
            return false; 
        }

        /// 
        ///  
        ///      Retrieves an editor of the requested type.
        ///  
        public override object GetEditor(Type editorBaseType) { 
            if (editorBaseType == typeof(UITypeEditor)) {
                if (editor == null) { 
                    editor = new AboutBoxUITypeEditor();
                }
            }
 
            return editor;
        } 
 
        /// 
        ///  
        ///     Retrieves the current value of the property on component,
        ///     invoking the getXXX method.  An exception in the getXXX
        ///     method will pass through.
        ///  
        public override object GetValue(object component) {
            return ""; 
        } 

        ///  
        /// 
        ///     Will reset the default value for this property on the component.  If
        ///     there was a default value passed in as a DefaultValueAttribute, that
        ///     value will be set as the value of the property on the component.  If 
        ///     there was no default value passed in, a ResetXXX method will be looked
        ///     for.  If one is found, it will be invoked.  If one is not found, this 
        ///     is a nop. 
        /// 
        public override void ResetValue(object component){ 
        }

        /// 
        ///  
        ///     This will set value to be the new value of this property on the
        ///     component by invoking the setXXX method on the component.  If the 
        ///     value specified is invalid, the component should throw an exception 
        ///     which will be passed up.  The component designer should design the
        ///     property so that getXXX following a setXXX should return the value 
        ///     passed in if no exception was thrown in the setXXX call.
        /// 
        [SuppressMessage("Microsoft.Usage", "CA2208:InstantiateArgumentExceptionsCorrectly")]
        public override void SetValue(object component, object value) { 
            throw new ArgumentException();
        } 
 
        /// 
        ///  
        ///     Indicates whether the value of this property needs to be persisted. In
        ///     other words, it indicates whether the state of the property is distinct
        ///     from when the component is first instantiated. If there is a default
        ///     value specified in this PropertyDescriptor, it will be compared against the 
        ///     property's current value to determine this.  If there is't, the
        ///     shouldPersistXXX method is looked for and invoked if found.  If both 
        ///     these routes fail, true will be returned. 
        ///
        ///     If this returns false, a tool should not persist this property's value. 
        /// 
        public override bool ShouldSerializeValue(object component) {
            return false;
        } 

        public class AboutBoxUITypeEditor : UITypeEditor { 
            ///  
            /// 
            ///      Edits the given object value using the editor style provided by 
            ///      GetEditorStyle.  A service provider is provided so that any
            ///      required editing services can be obtained.
            /// 
            public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value) { 
                     object component = context.Instance;
 
                     if (Marshal.IsComObject(component) && component is UnsafeNativeMethods.IDispatch) { 
                        UnsafeNativeMethods.IDispatch pDisp = (UnsafeNativeMethods.IDispatch)component;
                        NativeMethods.tagEXCEPINFO pExcepInfo = new NativeMethods.tagEXCEPINFO(); 
                        Guid g = Guid.Empty;

                        int hr = pDisp.Invoke(NativeMethods.ActiveX.DISPID_ABOUTBOX,
                                              ref g, 
                                              SafeNativeMethods.GetThreadLCID(),
                                              NativeMethods.DISPATCH_METHOD, 
                                              new NativeMethods.tagDISPPARAMS(), 
                                              null,
                                              pExcepInfo, null); 

                        Debug.Assert(NativeMethods.Succeeded(hr), "Failed to launch about box.");
                     }
                     return value; 
            }
 
            ///  
            /// 
            ///      Retrieves the editing style of the Edit method.  If the method 
            ///      is not supported, this will return None.
            /// 
            public override UITypeEditorEditStyle GetEditStyle(ITypeDescriptorContext context) {
                     return UITypeEditorEditStyle.Modal; 
            }
 
        } 
    }
} 

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

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