ControlDesigner.InvokeTransactedChange Method
Definition
Important
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Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host.
Overloads
InvokeTransactedChange(IComponent, TransactedChangeCallback, Object, String) |
Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host. |
InvokeTransactedChange(IComponent, TransactedChangeCallback, Object, String, MemberDescriptor) |
Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host. |
InvokeTransactedChange(IServiceProvider, IComponent, TransactedChangeCallback, Object, String, MemberDescriptor) |
Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host. |
InvokeTransactedChange(IComponent, TransactedChangeCallback, Object, String)
Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host.
public:
static void InvokeTransactedChange(System::ComponentModel::IComponent ^ component, System::Web::UI::Design::TransactedChangeCallback ^ callback, System::Object ^ context, System::String ^ description);
public static void InvokeTransactedChange (System.ComponentModel.IComponent component, System.Web.UI.Design.TransactedChangeCallback callback, object context, string description);
static member InvokeTransactedChange : System.ComponentModel.IComponent * System.Web.UI.Design.TransactedChangeCallback * obj * string -> unit
Public Shared Sub InvokeTransactedChange (component As IComponent, callback As TransactedChangeCallback, context As Object, description As String)
Parameters
- component
- IComponent
The control associated with the control designer.
- callback
- TransactedChangeCallback
A TransactedChangeCallback object representing a function to call in the control designer as part of the transaction.
- context
- Object
An object that contains the argument for callback.
- description
- String
A description of the effect of allowing the transaction to complete, which is used by the design host to give the user an opportunity to cancel the transaction.
Exceptions
Examples
The following code example demonstrates how to create a simple composite control with a Label and a TextBox control, together with properties to set the label text, and also the Text, Width, and BackColor properties of the TextBox control. An associated control designer class creates three DesignerActionMethodItem commands, each of which sets two properties on the control. By using the InvokeTransactedChange method, you can use the undo functionality of the design host, such as Visual Studio 2005, to roll back each completed transaction as a unit.
using System;
using System.Web;
using System.Web.UI;
using System.Drawing;
using System.Collections;
using System.Web.UI.WebControls;
using System.Web.UI.Design;
using System.ComponentModel;
using System.ComponentModel.Design;
namespace ASPNet.Samples
{
// Create a custom control class with a Label and TextBox
[System.Security.Permissions.PermissionSetAttribute(
System.Security.Permissions.SecurityAction.InheritanceDemand,
Name = "FullTrust")]
[System.Security.Permissions.PermissionSetAttribute(
System.Security.Permissions.SecurityAction.Demand,
Name = "FullTrust")]
[DesignerAttribute(typeof(SampleControlDesigner))]
public class SampleControl : CompositeControl
{
int defaultWidth = 150;
public SampleControl()
{
}
// Create a set of public properties
[Browsable(true), Bindable(true), DefaultValue(""),
PersistenceMode(PersistenceMode.Attribute)]
public string LabelText
{
get
{
EnsureChildControls();
return MyLabel.Text;
}
set
{
EnsureChildControls();
MyLabel.Text = value;
}
}
[Browsable(true), Bindable(true), DefaultValue(""),
PersistenceMode(PersistenceMode.Attribute)]
public string BoxText
{
get
{
EnsureChildControls();
return MyTextBox.Text;
}
set
{
EnsureChildControls();
MyTextBox.Text = value;
}
}
[Browsable(true), Bindable(true), Category("Appearance"),
PersistenceMode(PersistenceMode.Attribute)]
public Unit BoxWidth
{
get
{
EnsureChildControls();
return MyTextBox.Width;
}
set
{
EnsureChildControls();
MyTextBox.Width = value;
}
}
[Browsable(true), Bindable(true), Category("Appearance"),
PersistenceMode(PersistenceMode.Attribute)]
public override Color BackColor
{
get
{
EnsureChildControls();
return MyTextBox.BackColor;
}
set
{
EnsureChildControls();
MyTextBox.BackColor = value;
}
}
// Create private properties
private TextBox MyTextBox
{
get
{
EnsureChildControls();
return (TextBox)FindControl("MyTextBox");
}
}
private Label MyLabel
{
get
{
EnsureChildControls();
return (Label)FindControl("MyLabel");
}
}
// Create a label and a text box.
protected override void CreateChildControls()
{
// Clear the controls
Controls.Clear();
// Create a Label control
Label localLabel = new Label();
localLabel.EnableViewState = false;
localLabel.ID = "MyLabel";
localLabel.Text = localLabel.ID + ": ";
Controls.Add(localLabel);
// Create a TextBox control
TextBox localTextBox = new TextBox();
localTextBox.ID = "MyTextBox";
localTextBox.Width = defaultWidth;
Controls.Add(localTextBox);
}
}
// Create a designer class for the SampleControl
[System.Security.Permissions.SecurityPermission(
System.Security.Permissions.SecurityAction.Demand,
Flags = System.Security.Permissions.SecurityPermissionFlag.UnmanagedCode)]
public class SampleControlDesigner : ControlDesigner
{
// Constructor
public SampleControlDesigner() : base()
{
}
// Do not allow resizing; force use of properties to set width
public override bool AllowResize
{
get { return false; }
}
// Create a custom ActionLists collection
public override DesignerActionListCollection ActionLists
{
get
{
// Create the collection
DesignerActionListCollection actionLists = new DesignerActionListCollection();
// Get the base items, if any
actionLists.AddRange(base.ActionLists);
// Add a custom list of actions
actionLists.Add(new CustomControlActionList(this));
return actionLists;
}
}
// Create an embedded DesignerActionList class
private class CustomControlActionList : DesignerActionList
{
// Create private fields
private SampleControlDesigner _parent;
private DesignerActionItemCollection items;
// Constructor
public CustomControlActionList(SampleControlDesigner parent)
: base(parent.Component)
{
_parent = parent;
}
// Create a set of transacted callback methods
// Callback for the wide format
public void FormatWide()
{
SampleControl ctrl = (SampleControl)_parent.Component;
// Create the callback
TransactedChangeCallback toCall = new TransactedChangeCallback(DoFormat);
// Create the transacted change in the control
ControlDesigner.InvokeTransactedChange(ctrl, toCall, "FormatWide", "Use a wide format");
}
// Callback for the medium format
public void FormatMedium()
{
SampleControl ctrl = (SampleControl)_parent.Component;
// Create the callback
TransactedChangeCallback toCall = new TransactedChangeCallback(DoFormat);
// Create the transacted change in the control
ControlDesigner.InvokeTransactedChange(ctrl, toCall, "FormatMedium", "Use a medium format");
}
// Callback for the narrow format
public void FormatNarrow()
{
SampleControl ctrl = (SampleControl)_parent.Component;
// Create the callback
TransactedChangeCallback toCall = new TransactedChangeCallback(DoFormat);
// Create the transacted change in the control
ControlDesigner.InvokeTransactedChange(ctrl, toCall, "FormatNarrow", "Use a narrow format");
}
// Get the sorted list of Action items
public override DesignerActionItemCollection GetSortedActionItems()
{
if (items == null)
{
// Create the collection
items = new DesignerActionItemCollection();
// Add a header to the list
items.Add(new DesignerActionHeaderItem("Select a Style:"));
// Add three commands
items.Add(new DesignerActionMethodItem(this, "FormatWide", "Format Wide", true));
items.Add(new DesignerActionMethodItem(this, "FormatMedium", "Format Medium", true));
items.Add(new DesignerActionMethodItem(this, "FormatNarrow", "Format Narrow", true));
}
return items;
}
// Function for the callbacks to call
public bool DoFormat(object arg)
{
// Get a reference to the designer's associated component
SampleControl ctl = (SampleControl)_parent.Component;
// Get the format name from the arg
string fmt = (string)arg;
// Create property descriptors
PropertyDescriptor widthProp = TypeDescriptor.GetProperties(ctl)["BoxWidth"];
PropertyDescriptor backColorProp = TypeDescriptor.GetProperties(ctl)["BackColor"];
// For the selected format, set two properties
switch (fmt)
{
case "FormatWide":
widthProp.SetValue(ctl, Unit.Pixel(250));
backColorProp.SetValue(ctl, Color.LightBlue);
break;
case "FormatNarrow":
widthProp.SetValue(ctl, Unit.Pixel(100));
backColorProp.SetValue(ctl, Color.LightCoral);
break;
case "FormatMedium":
widthProp.SetValue(ctl, Unit.Pixel(150));
backColorProp.SetValue(ctl, Color.White);
break;
}
_parent.UpdateDesignTimeHtml();
// Return an indication of success
return true;
}
}
}
}
Imports System.Web
Imports System.Web.UI
Imports System.Drawing
Imports System.Collections
Imports System.Web.UI.WebControls
Imports System.Web.UI.Design
Imports System.ComponentModel
Imports System.ComponentModel.Design
Namespace ASPNet.Samples
' Create a custom control class with a Label and TextBox
<System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.InheritanceDemand, Name:="FullTrust")> _
<System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
<Designer("ASPNet.Samples.SampleControlDesigner")> _
Public Class SampleControl
Inherits CompositeControl
Dim defaultWidth As Integer = 150
Public Sub New()
End Sub
' Create a set of Public properties
<Bindable(True), DefaultValue(""), _
PersistenceMode(PersistenceMode.Attribute)> _
Public Property LabelText() As String
Get
EnsureChildControls()
Return MyLabel.Text
End Get
Set(ByVal value As String)
EnsureChildControls()
MyLabel.Text = value
End Set
End Property
<Bindable(True), DefaultValue(""), _
PersistenceMode(PersistenceMode.Attribute)> _
Public Property BoxText() As String
Get
EnsureChildControls()
Return MyTextBox.Text
End Get
Set(ByVal value As String)
EnsureChildControls()
MyTextBox.Text = value
End Set
End Property
<Bindable(True), Category("Appearance"), _
PersistenceMode(PersistenceMode.Attribute)> _
Public Property BoxWidth() As Unit
Get
EnsureChildControls()
Return MyTextBox.Width
End Get
Set(ByVal value As Unit)
EnsureChildControls()
MyTextBox.Width = value
End Set
End Property
<Bindable(True), Category("Appearance"), _
PersistenceMode(PersistenceMode.Attribute)> _
Public Overrides Property BackColor() As Color
Get
EnsureChildControls()
Return MyTextBox.BackColor()
End Get
Set(ByVal value As Color)
EnsureChildControls()
MyTextBox.BackColor = value
End Set
End Property
' Create private properties
Private ReadOnly Property MyTextBox() As TextBox
Get
EnsureChildControls()
Return CType(FindControl("MyTextBox"), TextBox)
End Get
End Property
Private ReadOnly Property MyLabel() As Label
Get
EnsureChildControls()
Return CType(FindControl("MyLabel"), Label)
End Get
End Property
' Create a Label and a TextBox
Protected Overrides Sub CreateChildControls()
Controls.Clear()
MyBase.CreateChildControls()
' Create a Label control
Dim localLabel As New Label()
localLabel.ID = "MyLabel"
localLabel.Text = localLabel.ID + ": "
localLabel.EnableViewState = False
Controls.Add(localLabel)
' Create a TextBox control
Dim localTextBox As New TextBox()
localTextBox.ID = "MyTextBox"
localTextBox.Width = defaultWidth
localTextBox.EnableViewState = False
Controls.Add(localTextBox)
End Sub
End Class
'-----------------------------------------------
' Create a designer class for the SampleControl
<System.Security.Permissions.SecurityPermission(System.Security.Permissions.SecurityAction.Demand, Flags:=System.Security.Permissions.SecurityPermissionFlag.UnmanagedCode)> _
Public Class SampleControlDesigner
Inherits ControlDesigner
Private sampControl As SampleControl
' Constructor
Public Sub New()
MyBase.New()
End Sub
' Do not allow resizing; force use of properties to set width
Public Overrides ReadOnly Property AllowResize() As Boolean
Get
Return False
End Get
End Property
' Create a custom ActionLists collection
Public Overrides ReadOnly Property ActionLists() As DesignerActionListCollection
Get
' Create the collection
Dim lists As New DesignerActionListCollection()
' Get the base items, if any
lists.AddRange(MyBase.ActionLists)
' Add my own list of actions
lists.Add(New CustomControlActionList(Me))
Return lists
End Get
End Property
' Create an embedded DesignerActionList class
Private Class CustomControlActionList
Inherits DesignerActionList
' Create private fields
Private _parent As SampleControlDesigner
Private _items As DesignerActionItemCollection
' Constructor
Public Sub New(ByVal parent As SampleControlDesigner)
MyBase.New(parent.Component)
_parent = parent
End Sub
' Create a set of transacted callback methods
' Callback for a wide format
Public Sub FormatWide()
Dim ctrl As SampleControl = CType(_parent.Component, SampleControl)
' Create the callback
Dim toCall As New TransactedChangeCallback(AddressOf DoFormat)
' Create the transacted change in the control
ControlDesigner.InvokeTransactedChange(ctrl, toCall, "FormatWide", "Use a wide format")
End Sub
' Callback for the medium format
Public Sub FormatMedium()
Dim ctrl As SampleControl = CType(_parent.Component, SampleControl)
' Create the callback
Dim toCall As New TransactedChangeCallback(AddressOf DoFormat)
' Create the transacted change in the control
ControlDesigner.InvokeTransactedChange(ctrl, toCall, "FormatMedium", "Use a medium format")
End Sub
' Callback for the narrow format
Public Sub FormatNarrow()
Dim ctrl As SampleControl = CType(_parent.Component, SampleControl)
' Create the callback
Dim toCall As New TransactedChangeCallback(AddressOf DoFormat)
' Create the transacted change in the control
ControlDesigner.InvokeTransactedChange(ctrl, toCall, "FormatNarrow", "Use a narrow format")
End Sub
' Get the sorted list of Action items
Public Overrides Function GetSortedActionItems() As DesignerActionItemCollection
If IsNothing(_items) Then
' Create the collection
_items = New DesignerActionItemCollection()
' Add a header to the list
_items.Add(New DesignerActionHeaderItem("Select a Style:"))
' Add three commands
_items.Add(New DesignerActionMethodItem(Me, "FormatWide", "Format Wide", True))
_items.Add(New DesignerActionMethodItem(Me, "FormatMedium", "Format Medium", True))
_items.Add(New DesignerActionMethodItem(Me, "FormatNarrow", "Format Narrow", True))
End If
Return _items
End Function
' Function for the callback to call
Public Function DoFormat(ByVal arg As Object) As Boolean
' Get a reference to the designer's associated component
Dim ctl As SampleControl = CType(_parent.ViewControl(), SampleControl)
' Get the format name from the arg
Dim fmt As String = CType(arg, String)
' Create property descriptors
Dim widthProp As PropertyDescriptor = TypeDescriptor.GetProperties(ctl)("BoxWidth")
Dim backColorProp As PropertyDescriptor = TypeDescriptor.GetProperties(ctl)("BackColor")
' For the selected format, set two properties
Select Case fmt
Case "FormatWide"
widthProp.SetValue(ctl, Unit.Pixel(250))
backColorProp.SetValue(ctl, Color.LightBlue)
Case "FormatNarrow"
widthProp.SetValue(ctl, Unit.Pixel(100))
backColorProp.SetValue(ctl, Color.LightCoral)
Case "FormatMedium"
widthProp.SetValue(ctl, Unit.Pixel(150))
backColorProp.SetValue(ctl, Color.White)
End Select
' Return an indication of success
Return True
End Function
End Class
End Class
End Namespace
Remarks
The implementation of the InvokeTransactedChange method notifies the design host, which is determined by the Site property of component
, that a change is occurring in the associated control and, if the change is not canceled by the design host, invokes the specified callback
using the specified context
, and then notifies the design host that the change has completed.
If the design host or the associated control throws a static Canceled
exception field of a CheckoutException exception, the transaction is canceled without invoking callback
.
See also
Applies to
InvokeTransactedChange(IComponent, TransactedChangeCallback, Object, String, MemberDescriptor)
Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host.
public:
static void InvokeTransactedChange(System::ComponentModel::IComponent ^ component, System::Web::UI::Design::TransactedChangeCallback ^ callback, System::Object ^ context, System::String ^ description, System::ComponentModel::MemberDescriptor ^ member);
public static void InvokeTransactedChange (System.ComponentModel.IComponent component, System.Web.UI.Design.TransactedChangeCallback callback, object context, string description, System.ComponentModel.MemberDescriptor member);
static member InvokeTransactedChange : System.ComponentModel.IComponent * System.Web.UI.Design.TransactedChangeCallback * obj * string * System.ComponentModel.MemberDescriptor -> unit
Public Shared Sub InvokeTransactedChange (component As IComponent, callback As TransactedChangeCallback, context As Object, description As String, member As MemberDescriptor)
Parameters
- component
- IComponent
The control associated with the control designer.
- callback
- TransactedChangeCallback
A TransactedChangeCallback object representing a function to call in the control designer as part of the transaction.
- context
- Object
An object that contains the argument for callback.
- description
- String
A description of the effect of allowing the transaction to complete, which is used by the design host to give the user an opportunity to cancel the transaction.
- member
- MemberDescriptor
A MemberDescriptor object (typically, either an EventDescriptor or a PropertyDescriptor object) that describes the member of the associated control that is being invoked as part of the transaction.
Exceptions
Examples
For a code example, see InvokeTransactedChange(IComponent, TransactedChangeCallback, Object, String).
Remarks
The implementation of the InvokeTransactedChange method notifies the design host, which is determined by the Site property of component
, that a change is occurring to the specified member
(property or method) of the associated control and, if the change is not canceled by the design host, invokes the specified callback
using the specified context
as the argument, and then notifies the design host that the change has completed.
If the design host or associated control throws a static Canceled
exception field of a CheckoutException exception, the transaction is canceled without invoking callback
.
See also
Applies to
InvokeTransactedChange(IServiceProvider, IComponent, TransactedChangeCallback, Object, String, MemberDescriptor)
Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host.
public:
static void InvokeTransactedChange(IServiceProvider ^ serviceProvider, System::ComponentModel::IComponent ^ component, System::Web::UI::Design::TransactedChangeCallback ^ callback, System::Object ^ context, System::String ^ description, System::ComponentModel::MemberDescriptor ^ member);
public static void InvokeTransactedChange (IServiceProvider serviceProvider, System.ComponentModel.IComponent component, System.Web.UI.Design.TransactedChangeCallback callback, object context, string description, System.ComponentModel.MemberDescriptor member);
static member InvokeTransactedChange : IServiceProvider * System.ComponentModel.IComponent * System.Web.UI.Design.TransactedChangeCallback * obj * string * System.ComponentModel.MemberDescriptor -> unit
Public Shared Sub InvokeTransactedChange (serviceProvider As IServiceProvider, component As IComponent, callback As TransactedChangeCallback, context As Object, description As String, member As MemberDescriptor)
Parameters
- serviceProvider
- IServiceProvider
An IServiceProvider object representing the design host that provides control designer services for the associated control.
- component
- IComponent
The control associated with the control designer.
- callback
- TransactedChangeCallback
A TransactedChangeCallback object representing a function to call in the control designer as part of the transaction.
- context
- Object
An object that contains the argument for callback.
- description
- String
A description of the effect of allowing the transaction to complete, which is used by the design host to give the user an opportunity to cancel the transaction.
- member
- MemberDescriptor
A MemberDescriptor object (typically either an EventDescriptor or a PropertyDescriptor object) that describes the member of the associated control that is being invoked as part of the transaction.
Exceptions
Examples
For a code example, see InvokeTransactedChange.
Remarks
The implementation of the InvokeTransactedChange method notifies the design host, which is represented by serviceProvider
, that a change is occurring to the specified member
(property or method) of the associated control and, if the change is not canceled by the design host, invokes the specified callback
using the specified context
as the argument, and then notifies the design host that the change has completed.
If the design host or the associated control throws a static Canceled
exception field of a CheckoutException exception, the transaction is canceled without invoking callback
.
See also
- IServiceProvider
- EventDescriptor
- PropertyDescriptor
- TransactedChangeCallback
- ASP.NET Control Designers Overview