/// <summary>
 /// 将当前声明写入到当前写入实例中。
 /// </summary>
 /// <param name="writer">当前写入实例中。</param>
 /// <param name="declaring">当前声明实例对象。</param>
 /// <param name="model">当前模型对象。</param>
 public virtual void Write(TextWriter writer, Declaring declaring, object model)
 {
     if (_comment)
     {
         return;
     }
     writer.Write(declaring.Parent.Indent());
     writer.WriteLine($"<!--{declaring.Declare}-->");
 }
        /// <summary>
        /// 将当前声明写入到当前写入实例中。
        /// </summary>
        /// <param name="writer">当前写入实例中。</param>
        /// <param name="declaring">当前声明实例对象。</param>
        /// <param name="model">当前模型对象。</param>
        public virtual void Write(TextWriter writer, Declaring declaring, object model)
        {
            var declare = declaring.Declare ?? "html";

            writer.WriteLine("<!DOCTYPE {0}>", declare);
        }