解决方法
How to make sure user does not select a date earlier than today or greater than today
可能存在您不希望用户选择比当前日期早一天的情况.例如：当您向用户提供表单以预订票证时,您不希望他选择较早的日期.要达到此要求,请使用以下JavaScript代码.
Prevent the User from selecting a Date Earlier than today
<head runat="server">
<title>Calendar Extender</title>
<script type="text/javascript">
function checkDate(sender,args)
{
if (sender._selectedDate < new Date())
{
alert("You cannot select a day earlier than today!");
sender._selectedDate = new Date();
// set the date back to the current date
sender._textBox.set_Value(sender._selectedDate.format(sender._format))
}
}
</script>
</head>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server" />
<div>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<cc1:CalendarExtender ID="CalendarExtender1"
runat="server" OnClientDateSelectionChanged="checkDate" TargetControlID="TextBox1" />
</div>
</form>
Select Date Greater than today
在javascript中,只需更改此行即可
sender._selectedDate>新日期()
注意：您可能会争辩说,用户仍然可以通过在文本框中输入或输入无效日期来更改日期.那么可以使用ValidationControl轻松处理,并在下一篇技巧中介绍.
Add validation to the CalendarExtender Control
向Calendar添加验证的一种简单方法是将ValidationControl添加到与CalendarExtender关联的文本框中.你有两个选择：
>将Extender添加到ValidationControl.为此,请拖放ValidationControl>点击ValidationControl的智能标签>选择添加扩展器.从Extender向导中,选择ValidatorCalloutExtender.使用此方法可以非常轻松地将控件扩展器发现并附加到控件上.在VS 2005中,您必须通过连接控制扩展器手动执行此过程.
>您可以选择不添加扩展器.
我们将继续使用选项A.我们将向TextBox添加两个ValidationControl.第一个是CompareValidator,用于检查用户是否未输入无效日期(例如：5月32日),第二个是RangeValidator,以根据需要保留日期范围.
添加CompareValidator
<asp:CompareValidator ID="CompareValidator1" runat="server"
ControlToValidate="TextBox1" Display="Dynamic" ErrorMessage="Invalid Date"
Operator="DataTypeCheck" Type="Date">
</asp:CompareValidator>
<cc1:ValidatorCalloutExtender ID="CompareValidator1_ValidatorCalloutExtender"
runat="server" Enabled="True" TargetControlID="CompareValidator1">
</cc1:ValidatorCalloutExtender>
Adding RangeValidator – We will restrict the user to select a date range starting from today to 15 days from now.
<asp:RangeValidator ID="RangeValidator1" runat="server"
ControlToValidate="TextBox1" ErrorMessage="RangeValidator"
Type="Date">
</asp:RangeValidator>
<cc1:ValidatorCalloutExtender ID="RangeValidator1_ValidatorCalloutExtender"
runat="server" Enabled="True" TargetControlID="RangeValidator1">
</cc1:ValidatorCalloutExtender>
protected void Page_Load(object sender,EventArgs e)
{
RangeValidator1.MinimumValue = System.DateTime.Now.ToShortDateString();
RangeValidator1.MaximumValue = System.DateTime.Now.AddDays(15).ToShortDateString();
}
VB.NET
Protected Sub Page_Load(ByVal sender As Object,ByVal e As EventArgs)
RangeValidator1.MinimumValue = System.DateTime.Now.ToShortDateString()
RangeValidator1.MaximumValue = System.DateTime.Now.AddDays(15).ToShortDateString()
End Sub
那些是与CalendarExtender相关的一些提示.随着工具包的未来版本的发布,我们应该希望能够以更简单的方式实现此功能.
来自：http://www.dotnetcurry.com/ShowArticle.aspx?ID=149
另一种高级方法是扩展CalendarExtender javascript,但是你有自己的自定义版本的ajax工具包.
http://codegoeshere.blogspot.com/2007/06/extending-calendarextender.html
