/// <summary>

         /// 文本框值 txtMD是一个Web TextBox

         /// </summary>

         [Bindable(true),

         Category("Appearance"),

         DefaultValue("")]

         public string Text

         {

              get

              {

                   if(txtMD.Text!="")

                       return txtMD.Text;

                   else

                       return "";

              }

              set

              {

                   txtMD.Text=value;

              }

         }

自定义属性：

/// <summary>

         /// 参考录入窗口宽度

         /// </summary>

         [Bindable(true),

         Category("Appearance"),

         DefaultValue("50")]

         public int TextBoxMaxLength

         {

              get

              {

                   return ViewState[this.UniqueID+"TextBoxMaxLength"]==null?50:(int)ViewState[this.UniqueID+"TextBoxMaxLength"];

              }

              set

              {

                   ViewState[this.UniqueID+"TextBoxMaxLength"]=value;

              }

         }