Create Pasted event in RadGridView

Environment

Product Version	Product	Author
2019.2.618	RadGridView for WinForms	Desislava Yordanova

Description

RadGridView offers the Pasting event which is appropriate for modifying the Clipboard data before pasting it in the grid. You can cancel this event as well in order to prevent pasting data in some cases.

A common requirement is to detect when the paste operation is completed in RadGridView. Note that the CellValidating/CellValidated events are fired after the paste operation. You can use a simple boolean flag which will be set to true in the Pasting event. Thus, you can detect when the CellValidating/CellValidated events are fired as a result from paste action.

However, this article will offer a solution how to create your own Pasted event.

Solution

In order to create a custom Pasted event in RadGridView, you need to:

• Create your own EventArgs (let's call the class PastedEventArgs) with the necessary properties, e.g. ClipboardData.
• Raise and consume an event that provides data. The EventHandler delegate is associated with the event, and an instance of a custom event data object is provided.
• Create a derivative of RadGridView and replace the default MasterGridViewTemplate with a custom one in which Paste method you should raise the Pasted event that is just defined.
• Replace the default RadGridView with the custom one in your project.

A full implementation is available in the following code snippet:

• C#
• VB.NET

public Form1()
{
    InitializeComponent();

    CustomMasterGridViewTemplate masterTemplate = this.radGridView1.MasterTemplate as CustomMasterGridViewTemplate;
    masterTemplate.Pasted += masterTemplate_Pasted;
}

private void masterTemplate_Pasted(object sender, PastedEventArgs e)
{
    Console.WriteLine(e.ClipboardData);
}

public class CustomGrid : RadGridView
{
    protected override RadGridViewElement CreateGridViewElement()
    {
        return new CustomRadGridViewElement();
    }

    public override string ThemeClassName
    {
        get
        {
            return typeof(RadGridView).FullName;
        }
    }
}

public class CustomRadGridViewElement : RadGridViewElement
{
    protected override MasterGridViewTemplate CreateTemplate()
    {
        return new CustomMasterGridViewTemplate();
    }

    protected override Type ThemeEffectiveType   
    {
        get  
        {
            return typeof(RadGridViewElement);   
        }
    }
}

public class CustomMasterGridViewTemplate : MasterGridViewTemplate
{
    public event EventHandler<PastedEventArgs> Pasted;

    protected virtual void OnPasted(string data)
    {
        if (Pasted != null)
            Pasted(this, new PastedEventArgs(data));
    }

    public override void Paste()
    {
        string data = Clipboard.GetData(DataFormats.UnicodeText).ToString();
        base.Paste();
        OnPasted(data);
    }
}

public class PastedEventArgs : EventArgs
{
    public PastedEventArgs(string clipboardData)
    {
        ClipboardData = clipboardData;
    }

    public string ClipboardData { get; private set; }
}

    Public Sub New()
        InitializeComponent()
        Dim masterTemplate As CustomMasterGridViewTemplate = TryCast(Me.RadGridView1.MasterTemplate, CustomMasterGridViewTemplate)
        AddHandler masterTemplate.Pasted, AddressOf masterTemplate_Pasted
    End Sub

    Private Sub masterTemplate_Pasted(ByVal sender As Object, ByVal e As PastedEventArgs)
        Console.WriteLine(e.ClipboardData)
    End Sub

    Public Class CustomGrid
    Inherits RadGridView

        Protected Overrides Function CreateGridViewElement() As RadGridViewElement
            Return New CustomRadGridViewElement()
        End Function

        Public Overrides Property ThemeClassName As String
            Get
                Return GetType(RadGridView).FullName
            End Get
            Set(value As String)
                MyBase.ThemeClassName = value
            End Set
        End Property
    End Class

    Public Class CustomRadGridViewElement
    Inherits RadGridViewElement

        Protected Overrides Function CreateTemplate() As MasterGridViewTemplate
            Return New CustomMasterGridViewTemplate()
        End Function

        Protected Overrides ReadOnly Property ThemeEffectiveType As Type
            Get
                Return GetType(RadGridViewElement)
            End Get
        End Property
    End Class

    Public Class CustomMasterGridViewTemplate
    Inherits MasterGridViewTemplate

        Public Event Pasted As EventHandler(Of PastedEventArgs)

        Protected Overridable Sub OnPasted(ByVal data As String)
            RaiseEvent Pasted(Me, New PastedEventArgs(data))
        End Sub

        Public Overrides Sub Paste()
            Dim data As String = Clipboard.GetData(DataFormats.UnicodeText).ToString()
            MyBase.Paste()
            OnPasted(data)
        End Sub
    End Class

    Public Class PastedEventArgs
    Inherits EventArgs

        Private _clipboardData As String
        Public Sub New(ByVal clipboardData As String)
            _clipboardData = clipboardData
        End Sub
        Public Property ClipboardData As String
            Get
                Return _clipboardData
            End Get
            Private Set(ByVal value As String)
                _clipboardData = value
            End Set
        End Property
    End Class