Flex loads file data streams

Flex loads file data streams

This article uses urlstream, URLRequest, and loader to load data streams. files can be images and SWF.

I. Flex code

<? XML version = "1.0" encoding = "UTF-8"?> <Br/> <mx: Application xmlns: MX = "http://www.adobe.com/2006/mxml" layout = "absolute"> <br/> <mx: SCRIPT> <br/> <! -- [CDATA [<br/> Import MX. controls. alert; <br/> Import MX. RPC. soap. loadevent; </P> <p> private var serverurl: String = "http: // localhost: 4051/website/downloadstreamfile. aspx "; <br/> private var stream: urlstream; <br/> private var Loader: loader; <br/> private function loadpicture (Event: mouseevent ): void <br/>{< br/> var URLRequest: URLRequest = new URLRequest (); <br/> stream = new urlstream (); </P> <p> URLRequest. u RL = serverurl + "? File00001.jpg "; <br/> stream. addeventlistener (event. complete, onurlrequesthandler); <br/> stream. load (URLRequest); <br/>}< br/> private function onurlrequesthandler (Event: Event): void <br/>{< br/> If (stream. connected) <br/>{< br/> var B: int; <br/> var Bytes: bytearray = new bytearray (); <br/> try <br/> {<br/> DO <br/> {<br/> B = stream. readbyte (); <br/> bytes. writebyte (B); <br/>}< br/> while (true); <br/>}< br/> catc H (E: eoferror) <br/>{}< br/>}</P> <p> // create the loader mask layer <br/> // var rect: shape = new shape (); <br/> // rect. graphics. beginfill (0 xffffff); <br/> // rect. graphics. drawrect (0, 0, 1000,100 0); <br/> // rect. graphics. endfill (); <br/> loader = new loader (); <br/> loader. addeventlistener (event. complete, onloaderhandler) <br/> loader. loadbytes (bytes); <br/> // loader. mask = rect; <br/> loader. alpha = 1; <br/> loader. cacheasbi TMAP = true; <br/> loader. rotation = 0; <br/> // the size of the loaded image cannot be obtained, the loader must be scaled to a certain level when the image size is predicted. <br/> loader. scalex= 0.6; <br/> loader. scaley = 0.6 <br/> // loader object can only have one sub-Display object and can only be loaded to an image or swfloader <br/> // image. addchild (loader); <br/> myswfloader. addchild (loader); <br/>}< br/> private function onloaderhandler (Event: Event): void <br/>{< br/> // loader. loadbytes () event. complete does not work ??!! <Br/> alert. show (loader. width. tostring (); <br/>}</P> <p> private function setsource (Event: mouseevent): void <br/>{< br/> var STR: string = "http: // localhost: 2286/GetFile. aspx? Pathpolicdydz200907&file=4.swf "; <br/> myswfloader. source = STR; <br/>}< br/>] --> <br/> </MX: SCRIPT> <br/> <mx: image x = "61" Y = "105" id = "image" width = "199" Height = "142"/> <br/> <mx: button x = "61" Y = "45" label = "load image" Click = "loadpicture (event)"/> <br/> <mx: button x = "436" Y = "45" label = "load to swfloader" Click = "setsource (event)"/> <br/> <mx: canvas x = "388" Y = "105"> <br/> <mx: swfloader id = "myswfloader" scalecontent = "true"/> <br/> </MX: canvas> <br/> </MX: Application> <br/>

Ii. file data flow code generated by httpservice

 Protected void page_load (Object sender, eventargs e) <br/>{< br/> string file = request ["file"]; <br/> If (string. isnullorempty (File) <br/> return; <br/> string filepath = server. mappath ("~ /Download/"+ file); <br/> If (file. exists (filepath) <br/> downloadstreamfile (filepath); <br/> response. end (); <br/>}</P> <p> // <summary> <br/> // download the file <br/> /// </Summary> <br />/// <Param name = "serverfilpath"> </param> <br/> /// <Param name = "FILENAME"> </param> <br/> public static void todownload (string serverfilpath, string filename) <br/>{< br/> filestream = new filestream (serverfilpath, filemode. open); <br/> long filesize = filestream. length; <br/> httpcontext. current. response. contenttype = "application/octet-stream"; <br/> httpcontext. current. response. addheader ("content-disposition", "attachment; filename = \" "+ utf_filename (filename) + "\";"); <br/> /// attachment --- download as an attachment <br/> /// inline --- Open Online <br/> httpcontext. current. response. addheader ("Content-Length", filesize. tostring (); <br/> byte [] filebuffer = new byte [filesize]; <br/> filestream. read (filebuffer, 0, (INT) filesize); <br/> httpcontext. current. response. binarywrite (filebuffer); <br/> filestream. close (); <br/> httpcontext. current. response. end (); <br/>}</P> <p> // <summary> <br/> // open the file <br/> /// </Summary> <br />/// <Param name = "serverfilpath"> </param> <br/> /// <Param name = "FILENAME"> </param> <br/> public static void toopen (string serverfilpath, string filename) <br/>{< br/> filestream = new filestream (serverfilpath, filemode. open); <br/> long filesize = filestream. length; <br/> httpcontext. current. response. contenttype = "application/octet-stream"; <br/> httpcontext. current. response. addheader ("content-disposition", "inline; filename = \" "+ utf_filename (filename) +" \ ";"); <br/> httpcontext. current. response. addheader ("Content-Length", filesize. tostring (); <br/> byte [] filebuffer = new byte [filesize]; <br/> filestream. read (filebuffer, 0, (INT) filesize); <br/> httpcontext. current. response. binarywrite (filebuffer); <br/> filestream. close (); <br/> httpcontext. current. response. end (); <br/>}</P> <p> Private Static string utf_filename (string filename) <br/>{< br/> return httputility. urlencode (filename, system. text. encoding. utf8 ); <br/>}</P> <p> // <summary> <br/> // download the file data stream <br/> /// </Summary> <br/> // <Param name = "serverfilpath"> </param> <br/> Public static void downloadstreamfile (string serverfilpath) <br/>{< br/> int blocksize = 1024*100; <br/> byte [] buffer = new byte [blocksize]; <br/> byte [] fileheader = new byte [101]; </P> <p> int startindex = 0; <br/> int bytesread = 0; <br/> int bytesfinish = 0; <br/> int filesize = 0; <br/> string headertext = string. empty; <br/> binaryreader breader = NULL; </P> <p> breader = new binaryreader (file. openread (serverfilpath); <br/> filesize = convert. toint32 (breader. basestream. length); </P> <p> while (bytesfinish <filesize) <br/> {<br/> If (bytesfinish + blocksize <filesize) <br/> bytesread = breader. read (buffer, startindex, blocksize); <br/> else <br/> bytesread = breader. read (buffer, startindex, filesize-bytesfinish); </P> <p> bytesfinish + = bytesread; <br/> httpcontext. current. response. outputstream. write (buffer, 0, bytesread); <br/>}< br/> breader. close (); <br/> httpcontext. current. response. end (); <br/>}

Note: The size of images and other files cannot be obtained during loading in this example, and the display is inaccurate.