flex:使用FileReference上传文件

<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" creationComplete="init()" width="1000" height="700" color="#25C1E2">?
<mx:Script>?
<![CDATA[?
private const defaultRequestUrl:String = "http://www.mysite.com/upload_ok.php";??????????
private var file : FileReference;?
private function init():void {?
Security.allowDomain("*");?
file = new FileReference();?
file.addEventListener(Event.SELECT,onFileSelect);?
file.addEventListener(ProgressEvent.PROGRESS,progressHandle);?
file.addEventListener(Event.COMPLETE,completeHandle);?
//file.addEventListener(Event.OPEN,openHandle);?
//file.addEventListener(IOErrorEvent.IO_ERROR,ioErrorHandler);?
??????????????????? //file.addEventListener(Event.CANCEL,cancelHandler);?
??????????????? }?
??????????????????
??????????????? private function onClickBrowserBtn() : void {?
??????????????????? file.browse(getTypeFilter());?
??????????????? private function getTypeFilter() : Array {?
??????????????????? var imagesFilter:FileFilter = new FileFilter("Images (*.jpg,*.jpeg,*.gif,*.png)","*.jpg;*.jpeg;*.gif;*.png");?
??????????????????? //var docFilter:FileFilter = new FileFilter("Documents","*.pdf;*.doc;*.txt");?
??????????????????????
??????????????????? return [imagesFilter];?
??????????????? private function onFileSelect(event : Event) : void {?
??????????????????? uploadBtn.enabled = true;?
??????????????????? infoText.htmlText = "Name: "+file.name+" "+"Size: "+file.size+" "+
??????????????????????? "Type: " + file.type + " " +???
??????????????????????? "Date: " + file.creationDate;?
??????????????? private function onClickUploadBtn() : void {?
??????????????????? var request : URLRequest = new URLRequest(defaultRequestUrl);?
??????????????????? request.data = "userId=123";?
??????????????????? file.upload(request);?
??????????????? private function progressHandle(event : ProgressEvent) : void {?
??????????????????? progressLabel.text = "complete " + event.bytesLoaded + " bytes";?
??????????????????? var fileUploadPercent : uint = event.bytesLoaded / event.bytesTotal * 100;?
??????????????????? uploadProgressBar.setProgress(fileUploadPercent,100);?
??????????????????? uploadProgressBar.label = "Complete " + fileUploadPercent + "%";?
??????????????? private function completeHandle(event : Event) : void {?
??????????????????? infoText.htmlText = "Upload " + file.name + " Complete!";?
??????????????????? uploadBtn.enabled = false;?
??????????? ]]>
??????? </mx:Script>?
??????????
??????? <mx:Button id="browserBtn" x="10" y="69" label="浏览" styleName="mylinkButton"???
??????????? click="onClickBrowserBtn()"/>?
??????????????
??????? <mx:Button id="uploadBtn" x="236" y="69" label="上传" enabled="false"???
??????????? click="onClickUploadBtn()"/>?
??????? <mx:ProgressBar id="uploadProgressBar" x="10" y="33" width="291"???
??????????? themeColor="#009dff" maximum="100" direction="right" mode="manual"/>?
??????? <mx:TextArea id="infoText" x="10" y="99" width="291" height="131"/>?
??????? <mx:Label id="progressLabel" x="10" y="10" width="291"/>?

?? </mx:Application>?

//------------------------分析--------------------------------
1 需要被上传的文件被声明为FileReference类

2 文件上传进度监控：file.addEventListener(ProgressEvent.PROGRESS,progressHandle);?
3 具体上传代码：
var request : URLRequest = new URLRequest(defaultRequestUrl);?
request.data = "userId=123";?
file.upload(request);?
注意：request.data属性设置为变量名和值组成的字符串，upload方法的参数为request
4 打开文件浏览窗口用：
file.browse(getTypeFilter());?
5 注意FileFilter的用法，它直接作为FileReference类的成员函数browse的参数
var imagesFilter:FileFilter = new FileFilter("Images (*.jpg,"*.jpg;*.jpeg;*.gif;*.png");?
6 注意进度条的用法：
private function progressHandle(event : ProgressEvent) : void {?
?????? progressLabel.text = "complete " + event.bytesLoaded + " bytes";?
?????? var fileUploadPercent : uint = event.bytesLoaded / event.bytesTotal * 100;?
?????? uploadProgressBar.setProgress(fileUploadPercent,100);?
?????? uploadProgressBar.label = "Complete " + fileUploadPercent + "%";?
}?
计算当前进度：
event.bytesLoaded / event.bytesTotal?
设置当前进度：
uploadProgressBar.setProgress(fileUploadPercent,STHeiti; font-size:14px; line-height:25px">显示当前进度：
<mx:ProgressBar id="uploadProgressBar" x="10" y="33" width="291"???
maximum="100" direction="right" mode="manual"/>

7、URLRequest的data属性可以与URLVariables类结合使用

1. ?urlVars = new URLVariables();
2. ? ? ? ? ? ? ? ? urlVars.userID = 94103;
3. ? ? ? ? ? ? ? ? urlVars.fpVersion = flash.system.Capabilities.version;
4. ?
5. ? ? ? ? ? ? ? ? urlReq = new URLRequest();
6. ? ? ? ? ? ? ? ? urlReq.method = URLRequestMethod.POST;
7. ? ? ? ? ? ? ? ? urlReq.data = urlVars;
8. ? ? ? ? ? ? ? ? urlReq.url = "http://localhost:8300/fileref/uploader.cfm";