private void OnClick(object sender, RoutedEventArgs e)
{
OpenFileDialog dialog = new OpenFileDialog
{
Filter = Filter,
Multiselect = false
};
if (dialog.ShowDialog() != true || !File.Exists(dialog.FileName))
{
return;
}
TextContent.Text = dialog.FileName;
TextContent.GetBindingExpression(TextBox.TextProperty)?.UpdateSource();
}