Microsoft.Office.Tools.Word.ContentControl ChkboxControl = vstoDoc.Controls.AddContentControl(textControlName, Microsoft.Office.Interop.Word.WdContentControlType.wdContentControlCheckBox);
                    ChkboxControl.Tag = textControlName;
                    if (String.IsNullOrEmpty(text) == false)
                    {
                        ChkboxControl.PlaceholderText = placeholderText;  //提示无法赋值  为只读的 那么这个怎么才能设置值呢
                        ChkboxControl.Title = text;
                    }