后台添加Textbox

        /// <summary>
        /// behind add textbox
        /// </summary>
        private void AddTextToTextBox()
        {
            TextBlock tb = new TextBlock();
            tb.TextWrapping = TextWrapping.Wrap;
            tb.Margin = new Thickness(10);
            tb.Inlines.Add("An example on ");
            tb.Inlines.Add(new Run("the TextBlock control ") { FontWeight = FontWeights.Bold });
            tb.Inlines.Add("using ");
            tb.Inlines.Add(new Run("inline ") { FontStyle = FontStyles.Italic });
            tb.Inlines.Add(new Run("text formatting ") { Foreground = Brushes.Blue });
            tb.Inlines.Add("from ");
            tb.Inlines.Add(new Run("Code-Behind") { TextDecorations = TextDecorations.Underline });
            tb.Inlines.Add(".");
            this.sp_text.Children.Add(tb);
        }