private void OpenFileRAWOnClick(object sender, RoutedEventArgs e) { OpenFileDialog ofd = new OpenFileDialog(); ofd.Filter = FileChecker.FileDialogRawFilter; ofd.FileOk += (o, args) => { if (FileChecker.IsBinary(ofd.FileName)) { MessageBox.Show("Binary files are not supported at this time.", "File is binary"); return; } if (FileChecker.IsTooBig(ofd.FileName)) { if (MessageBox.Show("Files with a size over 10MB are not supported.\nOpen anyways? (Program may freeze or stop working)", "File too big", MessageBoxButton.OKCancel) == MessageBoxResult.Cancel) { return; } } new MainWindow(ofd.FileName, typeof(TextEditor.TextEditorControl)).Show(); Close(); }; ofd.ShowDialog(); }