public TextProperties( 
   string text,
   string font,
   double fontSize,
   string fontStyle
)

TextProperties txtProp = new TextProperties("String", "Times New Roman", 24, "Regular");

//Update text element properties for an existing text element.

// Reference a layoutitem in a project by name
LayoutProjectItem layoutItem = Project.Current.GetItems<LayoutProjectItem>()
                      .FirstOrDefault(item => item.Name.Equals("MyLayout"));
if (layoutItem != null)
{

  //Perform on the worker thread
  QueuedTask.Run(() =>
  {
    // Reference and load the layout associated with the layout item
    Layout layout = layoutItem.GetLayout();
    if (layout != null)
    {
      // Reference a text element by name
      TextElement txtElm = layout.FindElement("MyTextElement") as TextElement;
      if (txtElm != null)
      {
        // Change placement properties
        txtElm.SetAnchor(Anchor.CenterPoint);
        txtElm.SetX(x);
        txtElm.SetY(y);

        // Change TextProperties
        TextProperties txtProperties = new TextProperties(
                         "Hello world", "Times New Roman", 48, "Regular");
        txtElm.SetTextProperties(txtProperties);
      }
    }
  });
}