Windows Forms Programming 
How to: Retrieve Data from the Clipboard 

The Clipboard class provides methods that you can use to interact with the Windows operating system Clipboard feature. Many applications use the Clipboard as a temporary repository for data. For example, word processors use the Clipboard during cut-and-paste operations. The Clipboard is also useful for transferring information from one application to another.

Some applications store data on the Clipboard in multiple formats to increase the number of other applications that can potentially use the data. A Clipboard format is a string that identifies the format. An application that uses the identified format can retrieve the associated data on the Clipboard. The DataFormats class provides predefined format names for your use. You can also use your own format names or use an object's type as its format. For information about adding data to the Clipboard, see How to: Add Data to the Clipboard.

To determine whether the Clipboard contains data in a particular format, use one of the ContainsFormat methods or the GetData method. To retrieve data from the Clipboard, use one of the GetFormat methods or the GetData method. These methods are new in Microsoft .NET Framework version 2.0.

To access data from the Clipboard by using versions earlier than .NET Framework 2.0, use the GetDataObject method and call the methods of the returned IDataObject. To determine whether a particular format is available in the returned object, for example, call the GetDataPresent method.

NoteNote

All Windows-based applications share the system Clipboard. Therefore, the contents are subject to change when you switch to another application.

The Clipboard class can only be used in threads set to single thread apartment (STA) mode. To use this class, ensure that your Main method is marked with the STAThreadAttribute attribute.

To retrieve data from the Clipboard in a single, common format

  • Use the GetAudioStream, GetFileDropList, GetImage, or GetText method. Optionally, use the corresponding ContainsFormat methods first to determine whether data is available in a particular format. These methods are available only in Microsoft .NET Framework version 2.0.

    Visual Basic 
    ' Demonstrates SetAudio, ContainsAudio, and GetAudioStream.
Public Function SwapClipboardAudio( _
    ByVal replacementAudioStream As System.IO.Stream) _
    As System.IO.Stream

    Dim returnAudioStream As System.IO.Stream = Nothing

    If (Clipboard.ContainsAudio()) Then
        returnAudioStream = Clipboard.GetAudioStream()
        Clipboard.SetAudio(replacementAudioStream)
    End If

    Return returnAudioStream

End Function

' Demonstrates SetFileDropList, ContainsFileDroList, and GetFileDropList
Public Function SwapClipboardFileDropList(ByVal replacementList _
    As System.Collections.Specialized.StringCollection) _
    As System.Collections.Specialized.StringCollection

    Dim returnList As System.Collections.Specialized.StringCollection _
        = Nothing

    If Clipboard.ContainsFileDropList() Then

        returnList = Clipboard.GetFileDropList()
        Clipboard.SetFileDropList(replacementList)
    End If

    Return returnList

End Function

' Demonstrates SetImage, ContainsImage, and GetImage.
Public Function SwapClipboardImage( _
    ByVal replacementImage As System.Drawing.Image) _
    As System.Drawing.Image

    Dim returnImage As System.Drawing.Image = Nothing

    If Clipboard.ContainsImage() Then
        returnImage = Clipboard.GetImage()
        Clipboard.SetImage(replacementImage)
    End If

    Return returnImage
End Function

' Demonstrates SetText, ContainsText, and GetText.
Public Function SwapClipboardHtmlText( _
    ByVal replacementHtmlText As String) As String

    Dim returnHtmlText As String = Nothing

    If (Clipboard.ContainsText(TextDataFormat.Html)) Then
        returnHtmlText = Clipboard.GetText(TextDataFormat.Html)
        Clipboard.SetText(replacementHtmlText, TextDataFormat.Html)
    End If

    Return returnHtmlText

End Function
    C# 
    // Demonstrates SetAudio, ContainsAudio, and GetAudioStream.
public System.IO.Stream SwapClipboardAudio(
    System.IO.Stream replacementAudioStream)
{
    System.IO.Stream returnAudioStream = null;
    if (Clipboard.ContainsAudio())
    {
        returnAudioStream = Clipboard.GetAudioStream();
        Clipboard.SetAudio(replacementAudioStream);
    }
    return returnAudioStream;
}

// Demonstrates SetFileDropList, ContainsFileDroList, and GetFileDropList
public System.Collections.Specialized.StringCollection
    SwapClipboardFileDropList(
    System.Collections.Specialized.StringCollection replacementList)
{
    System.Collections.Specialized.StringCollection returnList = null;
    if (Clipboard.ContainsFileDropList())
    {
        returnList = Clipboard.GetFileDropList();
        Clipboard.SetFileDropList(replacementList);
    }
    return returnList;
}

// Demonstrates SetImage, ContainsImage, and GetImage.
public System.Drawing.Image SwapClipboardImage(
    System.Drawing.Image replacementImage)
{
    System.Drawing.Image returnImage = null;
    if (Clipboard.ContainsImage())
    {
        returnImage = Clipboard.GetImage();
        Clipboard.SetImage(replacementImage);
    }
    return returnImage;
}

// Demonstrates SetText, ContainsText, and GetText.
public String SwapClipboardHtmlText(String replacementHtmlText)
{
    String returnHtmlText = null;
    if (Clipboard.ContainsText(TextDataFormat.Html))
    {
        returnHtmlText = Clipboard.GetText(TextDataFormat.Html);
        Clipboard.SetText(replacementHtmlText, TextDataFormat.Html);
    }
    return returnHtmlText;
}

To retrieve data from the Clipboard in a custom format

  • Use the GetData method with a custom format name. This method is available only in Microsoft .NET Framework version 2.0.

    You can also use predefined format names with the SetData method. For more information, see DataFormats.

    Visual Basic 
        ' Demonstrates SetData, ContainsData, and GetData
    ' using a custom format name and a business object.
    Public ReadOnly Property TestCustomFormat() As Customer
        Get
            Clipboard.SetData("CustomerFormat", New Customer("Customer Name"))

            If Clipboard.ContainsData("CustomerFormat") Then
                Return CType(Clipboard.GetData("CustomerFormat"), Customer)
            End If

            Return Nothing
        End Get
    End Property
<br /><span space="preserve">...</span><br />    <Serializable()> Public Class Customer

        Private nameValue As String = String.Empty

        Public Sub New(ByVal name As String)
            nameValue = name
        End Sub

        Public Property Name() As String
            Get
                Return nameValue
            End Get
            Set(ByVal value As String)
                nameValue = value
            End Set
        End Property

    End Class
    C# 
        // Demonstrates SetData, ContainsData, and GetData
    // using a custom format name and a business object.
    public Customer TestCustomFormat
    {
        get
        {
            Clipboard.SetData("CustomerFormat", new Customer("Customer Name"));
            if (Clipboard.ContainsData("CustomerFormat")) 
            {
                return Clipboard.GetData("CustomerFormat") as Customer;
            }
            return null;
        }
    }
<br /><span space="preserve">...</span><br />    [Serializable]
    public class Customer
    {
        private string nameValue = string.Empty;
        public Customer(String name)
        {
            nameValue = name;
        }
        public string Name
        {
            get { return nameValue; }
            set { nameValue = value; }
        }
    }

To retrieve data from the Clipboard in multiple formats

  • Use the GetDataObject method. You must use this method to retrieve data from the Clipboard on versions earlier than .NET Framework 2.0.

    Visual Basic 
        ' Demonstrates how to use a DataObject to add
    ' data to the Clipboard in multiple formats.
    Public Sub TestClipboardMultipleFormats()

        Dim data As New DataObject()

        ' Add a Customer object using the type as the format.
        data.SetData(New Customer("Customer as Customer object"))

        ' Add a ListViewItem object using a custom format name.
        data.SetData("CustomFormat", _
            New ListViewItem("Customer as ListViewItem"))

        Clipboard.SetDataObject(data)
        Dim retrievedData As DataObject = _
            CType(Clipboard.GetDataObject(), DataObject)

        If (retrievedData.GetDataPresent("CustomFormat")) Then

            Dim item As ListViewItem = _
                TryCast(retrievedData.GetData("CustomFormat"), ListViewItem)

            If item IsNot Nothing Then
                MessageBox.Show(item.Text)
            End If

        End If

        If retrievedData.GetDataPresent(GetType(Customer)) Then

            Dim customer As Customer = _
                CType(retrievedData.GetData(GetType(Customer)), Customer)

            If customer IsNot Nothing Then

                MessageBox.Show(customer.Name)
            End If

        End If

    End Sub
<br /><span space="preserve">...</span><br />    <Serializable()> Public Class Customer

        Private nameValue As String = String.Empty

        Public Sub New(ByVal name As String)
            nameValue = name
        End Sub

        Public Property Name() As String
            Get
                Return nameValue
            End Get
            Set(ByVal value As String)
                nameValue = value
            End Set
        End Property

    End Class
    C# 
        // Demonstrates how to use a DataObject to add
    // data to the Clipboard in multiple formats.
    public void TestClipboardMultipleFormats()
    {
        DataObject data = new DataObject();

        // Add a Customer object using the type as the format.
        data.SetData(new Customer("Customer as Customer object"));

        // Add a ListViewItem object using a custom format name.
        data.SetData("CustomFormat", 
            new ListViewItem("Customer as ListViewItem"));

        Clipboard.SetDataObject(data);
        DataObject retrievedData = (DataObject)Clipboard.GetDataObject();

        if (retrievedData.GetDataPresent("CustomFormat"))
        {
            ListViewItem item = 
                retrievedData.GetData("CustomFormat") as ListViewItem;
            if (item != null)
            {
                MessageBox.Show(item.Text);
            }
        }

        if (retrievedData.GetDataPresent(typeof(Customer)))
        {
            Customer customer = 
                retrievedData.GetData(typeof(Customer)) as Customer;
            if (customer != null)
            {
                MessageBox.Show(customer.Name);
            }
        }
    }
<br /><span space="preserve">...</span><br />    [Serializable]
    public class Customer
    {
        private string nameValue = string.Empty;
        public Customer(String name)
        {
            nameValue = name;
        }
        public string Name
        {
            get { return nameValue; }
            set { nameValue = value; }
        }
    }

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