功能：
可以应用到页面中的CheckBox上，通过为一组CheckBox指定同样的Key，让它们拥有类似单选按钮组(Radio Button Group)的行为，即用户只能选择组中的某一项。与单选按钮组不同的是，这个由CheckBox组成的单选按钮允许取消选择，即不选择组中的任意一项，而传统的单选按钮组则无法实现这个功能。
属性：
Key：隶属于同一群组的复选框，必须具有独一的键值。
TargetControlID：目标控件ID值。
实例代码：
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager ID="sm" runat="server" />
<table>
<tr>
<td colspan="2" >
外出旅游，您会携带‧‧‧
</td>
</tr>
<tr>
<td style="width: 165px" >
会携带
</td>
<td style="width: 165px" >
不会携带
</td>
</tr>
<tr>
<td>
<asp:CheckBox ID="chkBoxTakeCellPhone" runat="server" Text="手机" /><br />
<asp:CheckBox ID="chkBoxTakeCamera" runat="server" Text="相机" /><br />
<asp:CheckBox ID="chkBoxTakeMP3" runat="server" Text="MP3" /><br />
<asp:CheckBox ID="chkBoxTakeEraset" runat="server" Text="耳机" /><br />
<asp:CheckBox ID="chkBoxTakeNB" runat="server" Text="笔记本" /><br />
<asp:CheckBox ID="chkBoxTakeFlashDrive" runat="server" Text="随身听" /><br />
</td>
<td>
<asp:CheckBox ID="chkBoxNotTakeCellPhone" runat="server" Text="手机" /><br />
<asp:CheckBox ID="chkBoxNotTakeCamera" runat="server" Text="相机" /><br />
<asp:CheckBox ID="chkBoxNotTakeMP3" runat="server" Text="MP3" /><br />
<asp:CheckBox ID="chkBoxNotTakeEraset" runat="server" Text="耳机" /><br />
<asp:CheckBox ID="chkBoxNotTakeNB" runat="server" Text="笔记本" /><br />
<asp:CheckBox ID="chkBoxNotTakeFlashDrive" runat="server" Text="随身听" />
<br />
</td>
</tr>
<tr>
<td colspan="2">
<hr />
</td>
</tr>
</table>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeCellPhone"
runat="server"
TargetControlID="chkBoxTakeCellPhone"
Key="CellPhone">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeCellPhone"
runat="server"
TargetControlID="chkBoxNotTakeCellPhone"
Key="CellPhone">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<%-- 设定「相机」的互斥式复选框 --%>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeCamera"
runat="server"
TargetControlID="chkBoxTakeCamera"
Key="PDA">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakePDA"
runat="server"
TargetControlID="chkBoxNotTakeCamera"
Key="PDA">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<%-- 设定「MP3」的互斥式复选框 --%>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeMP3"
runat="server"
TargetControlID="chkBoxTakeMP3"
Key="MP3">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeMP3"
runat="server"
TargetControlID="chkBoxNotTakeMP3"
Key="MP3">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<%-- 设定「耳机」的互斥式复选框 --%>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeEarset"
runat="server"
TargetControlID="chkBoxTakeEraset"
Key="Eraset">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeEarset"
runat="server"
TargetControlID="chkBoxNotTakeEraset"
Key="Eraset">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<%-- 设定「笔记本」的互斥式复选框 --%>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeNB"
runat="server"
TargetControlID="chkBoxTakeNB"
Key="NB">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeNB"
runat="server"
TargetControlID="chkBoxNotTakeNB"
Key="NB">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeFlashDrive"
runat="server"
TargetControlID="chkBoxTakeFlashDrive"
Key="FlashDrive">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeFlashDrive"
runat="server"
TargetControlID="chkBoxNotTakeFlashDrive"
Key="FlashDrive">
</ajaxToolkit:MutuallyExclusiveCheckBoxExtender>
</form>
</body>
</html>
运行结果：
可以应用到页面中的CheckBox上，通过为一组CheckBox指定同样的Key，让它们拥有类似单选按钮组(Radio Button Group)的行为，即用户只能选择组中的某一项。与单选按钮组不同的是，这个由CheckBox组成的单选按钮允许取消选择，即不选择组中的任意一项，而传统的单选按钮组则无法实现这个功能。
属性：
Key：隶属于同一群组的复选框，必须具有独一的键值。
TargetControlID：目标控件ID值。
实例代码：
<html xmlns="http://www.w3.org/1999/xhtml"><head runat="server"> <title>Untitled Page</title></head><body> <form id="form1" runat="server"> <asp:ScriptManager ID="sm" runat="server" /> <table> <tr> <td colspan="2" > 外出旅游，您会携带‧‧‧ </td> </tr> <tr> <td style="width: 165px" > 会携带 </td> <td style="width: 165px" > 不会携带 </td> </tr> <tr> <td> <asp:CheckBox ID="chkBoxTakeCellPhone" runat="server" Text="手机" /><br /> <asp:CheckBox ID="chkBoxTakeCamera" runat="server" Text="相机" /><br /> <asp:CheckBox ID="chkBoxTakeMP3" runat="server" Text="MP3" /><br /> <asp:CheckBox ID="chkBoxTakeEraset" runat="server" Text="耳机" /><br /> <asp:CheckBox ID="chkBoxTakeNB" runat="server" Text="笔记本" /><br /> <asp:CheckBox ID="chkBoxTakeFlashDrive" runat="server" Text="随身听" /><br /> </td> <td> <asp:CheckBox ID="chkBoxNotTakeCellPhone" runat="server" Text="手机" /><br /> <asp:CheckBox ID="chkBoxNotTakeCamera" runat="server" Text="相机" /><br /> <asp:CheckBox ID="chkBoxNotTakeMP3" runat="server" Text="MP3" /><br /> <asp:CheckBox ID="chkBoxNotTakeEraset" runat="server" Text="耳机" /><br /> <asp:CheckBox ID="chkBoxNotTakeNB" runat="server" Text="笔记本" /><br /> <asp:CheckBox ID="chkBoxNotTakeFlashDrive" runat="server" Text="随身听" /> <br /> </td> </tr> <tr> <td colspan="2"> <hr /> </td> </tr> </table> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeCellPhone" runat="server" TargetControlID="chkBoxTakeCellPhone" Key="CellPhone"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeCellPhone" runat="server" TargetControlID="chkBoxNotTakeCellPhone" Key="CellPhone"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <%-- 设定「相机」的互斥式复选框 --%>
<ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeCamera" runat="server" TargetControlID="chkBoxTakeCamera" Key="PDA"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakePDA" runat="server" TargetControlID="chkBoxNotTakeCamera" Key="PDA"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <%-- 设定「MP3」的互斥式复选框 --%> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeMP3" runat="server" TargetControlID="chkBoxTakeMP3" Key="MP3"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeMP3" runat="server" TargetControlID="chkBoxNotTakeMP3" Key="MP3"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <%-- 设定「耳机」的互斥式复选框 --%> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeEarset" runat="server" TargetControlID="chkBoxTakeEraset" Key="Eraset"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeEarset" runat="server" TargetControlID="chkBoxNotTakeEraset" Key="Eraset"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <%-- 设定「笔记本」的互斥式复选框 --%> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeNB" runat="server" TargetControlID="chkBoxTakeNB" Key="NB"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeNB" runat="server" TargetControlID="chkBoxNotTakeNB" Key="NB"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeTakeFlashDrive" runat="server" TargetControlID="chkBoxTakeFlashDrive" Key="FlashDrive"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> <ajaxToolkit:MutuallyExclusiveCheckBoxExtender ID="mecbeNotTakeFlashDrive" runat="server" TargetControlID="chkBoxNotTakeFlashDrive" Key="FlashDrive"> </ajaxToolkit:MutuallyExclusiveCheckBoxExtender> </form></body></html>运行结果：
