第十五篇: Ajax Control Toolkit 控件包--4.AlwaysVisibleControlExtender

  
    

   
     
   
     div>
 
   
     <
   
     asp:UpdatePanel 
   
     ID
   
     ="UpdatePanel1"
   
      runat
   
     ="server"
   
     >
   
     
 
   
     <
   
     ContentTemplate
   
     >
   
     
 
   
     <
   
     asp:Panel 
   
     ID
   
     ="Panel1"
   
      runat
   
     ="server"
   
      Width
   
     ="161"
   
      Height
   
     ="127"
   
      
 BorderColor
   
     ="#C2C2C2"
   
      BorderStyle
   
     ="Dashed"
   
      BorderWidth
   
     ="1px"
   
     >
   
     
 
   
     <
   
     br 
   
     />
   
     
 
   
     <
   
     br 
   
     />
   
     
 学习AJAX
   
     <
   
     br
   
     />
   
     
 就去playaspx.com
   
     </
   
     asp:Panel
   
     >
   
     
 
   
     <
   
     cc1:AlwaysVisibleControlExtender 
   
     ID
   
     ="AlwaysVisibleControlExtender1"
   
      
 runat
   
     ="server"
   
      TargetControlID
   
     ="Panel1"
   
      VerticalSide
   
     ="Middle"
   
     >
   
     
 
   
     </
   
     cc1:AlwaysVisibleControlExtender
   
     >
   
     
 
 
   
     <
   
     asp:DropDownList 
   
     ID
   
     ="DropDownList1"
   
      runat
   
     ="server"
   
      AutoPostBack
   
     ="True"
   
      
 onselectedindexchanged
   
     ="DropDownList1_SelectedIndexChanged"
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="None"
   
     >
   
     默认
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="00"
   
     >
   
     左上
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="01"
   
     >
   
     左中
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="02"
   
     >
   
     左下
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="10"
   
     >
   
     中上
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="11"
   
     >
   
     中中
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="12"
   
     >
   
     中下
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="20"
   
     >
   
     右上
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="21"
   
     >
   
     右中
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     <
   
     asp:ListItem 
   
     Value
   
     ="22"
   
     >
   
     右下
   
     </
   
     asp:ListItem
   
     >
   
     
 
   
     </
   
     asp:DropDownList
   
     >
   
     
 
   
     </
   
     ContentTemplate
   
     >
   
     
 
   
     </
   
     asp:UpdatePanel
   
     >
  
    

 

  
    

   
     
   
      
   
     protected
   
      
   
     void
   
      DropDownList1_SelectedIndexChanged(
   
     object
   
      sender, EventArgs e)
 {
 
   
     switch
   
      (DropDownList1.SelectedValue[
   
     0
   
     ].ToString())
 { 
 
   
     case
   
      
   
     "
   
     0
   
     "
   
     :
 AlwaysVisibleControlExtender1.HorizontalSide 
   
     =
   
      HorizontalSide.Left;
 
   
     break
   
     ;
 
   
     case
   
      
   
     "
   
     1
   
     "
   
     :
 AlwaysVisibleControlExtender1.HorizontalSide 
   
     =
   
      HorizontalSide.Center;
 
   
     break
   
     ;
 
   
     case
   
      
   
     "
   
     2
   
     "
   
     :
 AlwaysVisibleControlExtender1.HorizontalSide 
   
     =
   
      HorizontalSide.Right;
 
   
     break
   
     ;
 
   
     default
   
     :
 AlwaysVisibleControlExtender1.HorizontalSide 
   
     =
   
      HorizontalSide.Center;
 
   
     break
   
     ;
 }
 
   
     switch
   
      (DropDownList1.SelectedValue[
   
     1
   
     ].ToString())
 { 
 
   
     case
   
      
   
     "
   
     0
   
     "
   
     :
 AlwaysVisibleControlExtender1.VerticalSide 
   
     =
   
      VerticalSide.Top;
 
   
     break
   
     ;
 
   
     case
   
      
   
     "
   
     1
   
     "
   
     :
 AlwaysVisibleControlExtender1.VerticalSide 
   
     =
   
      VerticalSide.Middle;
 
   
     break
   
     ;
 
   
     case
   
      
   
     "
   
     2
   
     "
   
     :
 AlwaysVisibleControlExtender1.VerticalSide 
   
     =
   
      VerticalSide.Bottom;
 
   
     break
   
     ;
 
   
     default
   
     :
 AlwaysVisibleControlExtender1.VerticalSide 
   
     =
   
      VerticalSide.Middle;
 
   
     break
   
     ;
 }
 }
  
    

常用属性:

 1、TargetControlID: 需要保持’悬浮’状态的控件ID.

 2、HorizontalSide: 被控制控件的水平位置,可以为Left, Center,Right,默认值是Left.

 3、HorizontalOffset: 结合上面的horizontalSide来使用,如果horizontalSide为Left,那么把HorizontalOffset设置为10px,表示距离浏览器左边10px。

 4、VerticalSide: 被控制控件的垂直位置,可以为Top,Middle,Bottom。 默认值是Top.

 5、VertivcalOffset: 和上面的VerticalSide结合控制控件距离VerticalSide多少像素。如果VerticalSide设置为Top, VerticalOffset设置为20px,那么表示控件距离Top的距离是20px.

 6、ScrollEffectDuration: 滚动效果周期设置,我不大清楚有什么用处。

 CS代码，引入命名空间 using AjaxControlToolkit;