ToolboxItem-Konstruktor ()

Initialisiert eine neue Instanz der ToolboxItem-Klasse.

Namespace: System.Drawing.Design
Assembly: System.Drawing (in system.drawing.dll)

Syntax

'Declaration
Public Sub New
'Usage
Dim instance As New ToolboxItem

public ToolboxItem ()

public:
ToolboxItem ()

public ToolboxItem ()

public function ToolboxItem ()

Beispiel

Im folgenden Codebeispiel wird die Verwendung des ToolboxItem-Konstruktors in einer von ToolboxItem abgeleiteten Klasse für die Implementierung eines benutzerdefinierten Toolboxelements veranschaulicht. Dieses Codebeispiel ist Teil eines umfangreicheren Beispiels für die ToolboxItem-Klasse.

<Serializable()> _
Class MyToolboxItem
    Inherits ToolboxItem

    ' The add components dialog in Visual Studio looks for a public
    ' constructor that takes a type.
    Public Sub New(ByVal toolType As Type)
        MyBase.New(toolType)
    End Sub


    ' And you must provide this special constructor for serialization.
    ' If you add additional data to MyToolboxItem that you
    ' want to serialize, you may override Deserialize and
    ' Serialize methods to add that data.  
    Sub New(ByVal info As SerializationInfo, _
        ByVal context As StreamingContext)
        Deserialize(info, context)
    End Sub


    ' Let's override the creation code and pop up a dialog.
    Protected Overrides Function CreateComponentsCore( _
        ByVal host As System.ComponentModel.Design.IDesignerHost, _
        ByVal defaultValues As System.Collections.IDictionary) _
        As IComponent()
        ' Get the string we want to fill in the custom
        ' user control.  If the user cancels out of the dialog,
        ' return null or an empty array to signify that the 
        ' tool creation was canceled.
        Dim d As New ToolboxItemDialog()
        If d.ShowDialog() = DialogResult.OK Then
            Dim [text] As String = d.CreationText
            Dim comps As IComponent() = _
                MyBase.CreateComponentsCore(host, defaultValues)
            ' comps will have a single component: our data type.
            CType(comps(0), UserControl1).LabelText = [text]
            Return comps
        Else
            Return Nothing
        End If
    End Function
End Class

// Toolbox items must be serializable.
[Serializable]
class MyToolboxItem : ToolboxItem
{
    // The add components dialog in Visual Studio looks for a public
    // constructor that takes a type.
    public MyToolboxItem(Type toolType)
        : base(toolType)
    {
    }

    // And you must provide this special constructor for serialization.
    // If you add additional data to MyToolboxItem that you
    // want to serialize, you may override Deserialize and
    // Serialize methods to add that data.  
    MyToolboxItem(SerializationInfo info, StreamingContext context)
    {
        Deserialize(info, context);
    }

    // Let's override the creation code and pop up a dialog.
    protected override IComponent[] CreateComponentsCore(
        System.ComponentModel.Design.IDesignerHost host, 
        System.Collections.IDictionary defaultValues)
    {
        // Get the string we want to fill in the custom
        // user control.  If the user cancels out of the dialog,
        // return null or an empty array to signify that the 
        // tool creation was canceled.
        ToolboxItemDialog d = new ToolboxItemDialog();
        if (d.ShowDialog() == DialogResult.OK)
        {
            string text = d.CreationText;

            IComponent[] comps = 
                base.CreateComponentsCore(host, defaultValues);
            // comps will have a single component: our data type.
            ((UserControl1)comps[0]).LabelText = text;
            return comps;
        }
        else
        {
            return null;
        }
    }
}

Plattformen

Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

Siehe auch

Referenz

ToolboxItem-Klasse
ToolboxItem-Member
System.Drawing.Design-Namespace