C# Invalid FORMATETC structure when using GetTextAsync

Question

I'm trying to make a progam which automatically searches for the word I copied in a file and then replaces that word in the clipboard with the line on which it was found in my file. I successfully setup an Eventhandler to see when the clipboard changes. I'm now trying to implement a way of reading my file.

After trying to use the StringReader the Exception is thrown:

Invalid FORMATETC structure occurred.

This is my code right now:

public partial class MainWindow : System.Windows.Window
{
    string line;
    string currentClipboardContent;
    string expectedClipboardContent;
    string vocabularygerman = Properties.Resources.vocabularygerman;
    string vocabularyfrench = Properties.Resources.vocabularyfrench;
    int lineNumber;

    public MainWindow()
    {
        InitializeComponent();
        Windows.ApplicationModel.DataTransfer.Clipboard.ContentChanged += new EventHandler<object>(this.TrackClipboardChanges_EventHandler);
    }

    private async void TrackClipboardChanges_EventHandler(object sender, object e)
    {
        DataPackageView dataPackageView = Windows.ApplicationModel.DataTransfer.Clipboard.GetContent();
        if (dataPackageView.Contains(StandardDataFormats.Text))
        {
            currentClipboardContent = await dataPackageView.GetTextAsync();
            if (expectedClipboardContent != currentClipboardContent)
            {
                Thread.Sleep(500);

                
                using (var reader = new StringReader(vocabularygerman))
                {
                    lineNumber = 0;
                    while ((line = reader.ReadLine()) != null)
                    {
                        lineNumber++;
                        if (line.Contains(currentClipboardContent))
                        {
                            System.Windows.Forms.Clipboard.SetDataObject(lineNumber);
                            break;
                        }
                    }
                }
                expectedClipboardContent = System.Windows.Forms.Clipboard.GetText();
            }
        }
    }

Everything worked fine until I tried to use the StringReader. I'm thinking of ditching the stringreader altogether and using a streamreader, but I am not able to use my vocabularygerman.txt file in my resources.

Answer 1

StringReader does not implement the IDataObject interface so SetDataObject method wont like that as it depends on that interface being present.

Try

Clipboard.SetText(lineNumber.ToString())

instead if you need the StringReader.

PS: use await for async calls