string sourceData = "Some string data to store...";
    byte[] unicodeText = Encoding.Unicode.GetBytes(sourceData);
    byte[] utf8Text = Encoding.UTF8.GetBytes(sourceData);

    string uniCodeFormat = "Unicode";
    string utf8DataFormat = "UTF-8";
            
    DragDropEventData dataObject = e.Data as DragDropEventData;
    dataObject.SetData(sourceData);
    dataObject.SetData(uniCodeFormat, unicodeText);
    dataObject.SetData(utf8DataFormat, utf8Text);

    // Get an array of strings, each string denoting a data format
    // that is available in the data object.  This overload of GetDataFormats
    // returns all available data formats, native and auto-convertible.
    string[] dataFormats = dataObject.GetFormats();

    // Get the number of data formats present in the data object, including both
    // auto-convertible and native data formats.
    int numberOfDataFormats = dataFormats.Length;

    // To enumerate the resulting array of data formats, and take some action when
    // a particular data format is found, use a code structure similar to the following.
    foreach (string dataFormat in dataFormats)
    {
        if (dataFormat == uniCodeFormat)
        {
            // Take some action if/when data in the Text data format is found.
            break;
        }
        else if (dataFormat == utf8DataFormat)
        {
            // Take some action if/when data in the string data format is found.
            break;
        }
    }