flex---->Flex 登录实例

<?xml version="1.0" encoding="utf-8"?>

<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" creationComplete="initApp()">
 <mx:states>
  <mx:State name="LoginNewState">
   <mx:RemoveChild target="{panel}"/>
   <mx:AddChild position="lastChild">
    <mx:Label text="欢迎进入第一个Flex主页！" width="488" height="67" fontSize="22" fontFamily="Georgia" textAlign="center" alpha="1.0" fontStyle="normal" horizontalCenter="35" verticalCenter="31" color="#F5B333"/>
   </mx:AddChild>
   <mx:SetStyle name="color" value="#51DBF9"/>
  </mx:State>
 </mx:states>
<mx:Script>
 <![CDATA[
  import mx.controls.Alert;
  
  //验证登陆
  private function loginHandle():void
  {
   if(txtUsername.text==""||txtPassword.text==""){
    Alert.show("请输入用户名和密码！");
   }else{
    if(txtUsername.text=="admin"&&txtPassword.text=="123"
    &&txtCheckCode.text.toLowerCase()== lblCheckCode.text.toLowerCase()){
     Alert.show("登陆成功！");
     currentState="LoginNewState";
    }else{
     if(txtCheckCode.text.toLowerCase()!= lblCheckCode.text.toLowerCase()){
      
     Alert.show("验证码错误！");
     lblCheckCode.text=GrearateCheckCode();
     }else{
      
     Alert.show("用户名和密码错误！");
     }
     
    }
   }
  }
  //重置表单数据
  private function resetHandle():void
  {
   txtUsername.text="";
   txtPassword.text="";
  }
  
  //该函数是应用程序（Application）在初始化的时候就执行。
  private function initApp():void{
   //显示验证码
   lblCheckCode.text=GrearateCheckCode();
  }
  
  private function GrearateCheckCode():String{
   
   //定义变量
   var ran:Number;//0-1的随机数
   var number:Number;//是ran的10000倍的数
   var code:String;//生成单个的字母
   var checkCode:String="";//返回的验证码
   
   //生成四个随机数（转换为字符）
   for(var i:int=0;i<4;i++){
    ran=Math.random();
    number=Math.round(ran*10000);
    
    if(number%2==0){
    
    //通过fromCharCode（）是用ASCII码来给字符串赋值，返回一个字母
    code=String.fromCharCode(48+(number%10));
    }
    else{
    code=String.fromCharCode(65+(number%26)); 
    }
    checkCode+=code;
    
   }
   return checkCode;
  }
 ]]>
</mx:Script> 
 <mx:Panel width="318" height="210" layout="absolute" title="Flex登陆界面" id="panel"
  horizontalAlign="center" verticalAlign="middle" color="#1894AF"
  fontFamily="Georgia" horizontalCenter="-7" verticalCenter="-13" fontSize="12" themeColor="#0356FE" fontWeight="normal">
 
  <mx:Label x="36" y="29" text="用户名:" fontSize="12"/>
  <mx:Label x="36" y="60" text="密   码:" width="45" fontSize="12"/>
  <mx:TextInput x="93" y="27" id="txtUsername"/>
  <mx:TextInput x="93" y="58" id="txtPassword" displayAsPassword="true" editable="true"/>
  <mx:Button x="95" y="130" label="登陆" id="btnLogin" click="loginHandle();"  fontSize="12" fontWeight="bold"/>
  <mx:Button x="177" y="130" label="重置" id="btnReset" click="resetHandle();" fontSize="12"/>
  <mx:Text x="34" y="91" text="验证码:" width="54" fontSize="12"/>
  <mx:TextInput x="94" y="89" width="49" id="txtCheckCode" fontSize="12"/>
  <mx:Text x="152" y="91" width="47" id="lblCheckCode" fontSize="14"/>
  <mx:LinkButton x="199" y="89" label="看不清？" width="71" id="LinkbtnReGreateCode" click="lblCheckCode.text=GrearateCheckCode()" fontSize="12" fontWeight="normal"/>
 </mx:Panel>
</mx:Application>