Custom Clipboard Format for Copy\Paste

[Chris]

We have an application in which we would like to support a custom clipboard format for copying\pasting in a RadRichTextBox. I have read your article on clipboard support (http://docs.telerik.com/devtools/wpf/controls/radrichtextbox/features/clipboard-support), but that seems to mainly deal with changing which provided clipboard formats are used.

It appears that if I register a custom format provider with ClipboardEx, that would be able to handle pasting the custom format. For example:

ClipboardEx.ClipboardHandlers.Insert(0, new ClipboardHandler()
{
    ClipboardDataFormat = "MyCustomDataFormat",
    DocumentFormatProvider = new MyCustomFormatProvider()
});

 

However, I don't see a way to handle copying a custom format without intercepting the CopyExecutingCommand and adding the custom format the the clipboard. For example:

void RadRichTextBox_CommandExecuting(object sender, CommandExecutingEventArgs e)
{
    if (e.Command is CopyCommand)
    {
        Clipboard.SetData("MyCustomDataFormat", GetSelectionAsCustomDataFormatString());
    }
}

However, I would want to make sure that the default clipboard formats are still added to the clipboard in addition to our custom format.

Can you provide any guidance on the best way to handle copying and pasting a custom clipboard format?

Thank you.

[Boby]

Hello Chris,

You can use CommandExecuted event,  "clone" the original data object and enhance it with the custom format, e.g.:

this.radRichTextBox.CommandExecuted += (sender, e) =>
{
    if (e.Command is CopyCommand)
    {
        var originalDataObject = Clipboard.GetDataObject();

        DataObject dataObject = new DataObject();
        foreach (string format in originalDataObject.GetFormats())
        {
            dataObject.SetData(format, originalDataObject.GetData(format));
        }

        dataObject.SetData("Html", new HtmlFormatProvider().Export(this.radRichTextBox.Document));

        Clipboard.SetDataObject(dataObject);
    }
};

Your assumption that registered handlers should be used for copying as well is actually very reasonable. I logged it as a feature request in our public feedback portal here: RichTextBox: Enhance clipboard handlers API and use them for Copy operation. We have added some points to your account for the suggestion. 

Regards,
Boby
Telerik by Progress

[Chris]

Thank you for your help. That works for putting data on the clipboard. However, my custom clipboard handler is not being used. It appears that if there is a format of RadDocumentGUID on the clipboard, all of the clipboard handlers are ignored. I was able to get around this by modifying the code you provided to use the following foreach.

foreach (string format in originalDataObject.GetFormats().Where(f => f != "RadDocumentGUID"))
{
    dataObject.SetData(format, originalDataObject.GetData(format));
}

 

Is there a better way to handle this?

[Boby]

Hello Chris,

Current Paste implementation always uses the native RadDocument format for copy-pasting between RadRichTextBoxes, and this is not subject to configuring with ClipboardHandlers - so your approach will do the work - if RadDocumentGUID is not present in the clipboard data, the first registered clipboard handler will be used. 

Regards,
Boby
Telerik by Progress