Flex DateField 日期范围

    开始日期 与 结束日期的范围选择
    两者都不能大于今天，开始日期不能大于结束日期

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="vertical" backgroundGradientColors="[#ffffff, #ffffff]">
        <mx:Script>
                <![CDATA[
                        import mx.controls.DateField;
                        
                        [Bindable]
                        private var today:Date = new Date(new Date().setHours(0,0,0,0));
                        [Bindable]
                        private var start:Date = today;
                        [Bindable]
                        private var end:Date = start;
                        
                        //=======================================
                        //Event Handler
                        //=======================================
                        
                        /*DateChange*/
                        private function onDateChangeHandler(event:Event):void
                        {
                                //var currentDF:DateField = DateField(event.currentTarget);
                                
                                
                                if(startDF.text == "")
                                {
                                        startDF.selectedDate = start;
                                }
                                else
                                {
                                        start = startDF.selectedDate;        
                                }
                                
                                if(endDF.text == "")
                                {
                                        endDF.selectedDate = this.end;
                                }
                                else
                                {
                                        this.end = endDF.selectedDate;
                                }
                                
                        }                        
                        
                ]]>
        </mx:Script>
        <mx:ApplicationControlBar width="446" dock="true">
                <mx:Label text="开始日期：" />
                <mx:DateField id="startDF"  showToday="true"  selectedDate="{start}" formatString="YYYY年MM月DD日"
                        selectableRange="{{rangeEnd:end}}" change="onDateChangeHandler(event)"/>
                        
                <mx:Label text="结束日期："/>
                <mx:DateField id="endDF" showToday="true" selectedDate="{end}" formatString="YYYY年MM月DD日"
                        selectableRange="{{rangeStart:start,rangeEnd:today}}" change="onDateChangeHandler(event)"/>
        </mx:ApplicationControlBar>
        
</mx:Application>