编程在Android上下载一个文件 [英] Download a file programatically on Android

问题描述

我是从Web服务器下载文件编程。下载完成后，我检查了锉的大小，扩展和其他所有参数都是正确的，但我当我尝试播放的媒体播放器则表明它已损坏的文件。

plz帮助..

code：

 字节[] B = NULL;
    在的InputStream = NULL;
    B =新的字节[的Integer.parseInt（尺寸）]。 //该文件的大小。
    在= OpenHttpConnection（URL）;
    in.read（B）;
    附寄（）;

    文件夹=新的文件（/ SD卡，文件夹）;
   布尔查= folder.mkdirs（）;

   Log.d（HttpDownload，检查+查）;

   myfile文件=新的文件（/ SD卡/文件夹/+姓名）;


    myFile.createNewFile（）;
   的OutputStream filoutputStream =新的FileOutputStream（MYFILE）;

   filoutputStream.write（B）;

   filoutputStream.flush（）;

   filoutputStream.close（）;
 

解决方案

这是一些工作code我有下载指定的URL给定的文件对象。 File对象（OUTPUTFILE）刚刚用新的文件（路径）创建的，我没有叫createNewFile或任何东西。

 私有静态无效downloadFile（字符串URL，文件OUTPUTFILE）{
  尝试 {
      网址U =新的网址（URL）;
      URLConnection的康恩= u.openConnection（）;
      INT CONTENTLENGTH = conn.getContentLength（）;

      的DataInputStream流=新的DataInputStream（u.openStream（））;

        byte []的缓冲区=新的字节[CONTENTLENGTH]
        stream.readFully（缓冲液）;
        stream.close（）;

        DataOutputStream类FOS =新DataOutputStream类（新的FileOutputStream（OUTPUTFILE））;
        fos.write（缓冲液）;
        fos.flush（）;
        fos.close（）;
  }赶上（FileNotFoundException异常E）{
      返回; //吞下404
  }赶上（IOException异常E）{
      返回; //吞下404
  }
}
 

i am downloading files from web server programatically. after download is complete, i checked the file.the size ,extension and all other parameters are correct but i when i try to play that file in media player it is showing that it is corrupt.

plz help..

code:

    byte[] b = null;
    InputStream in = null;
    b = new byte[Integer.parseInt(size)];    // size of the file.
    in = OpenHttpConnection(URL);            
    in.read(b);
    in.close();

    File folder = new File("/sdcard", "folder");
   boolean check = folder.mkdirs();

   Log.d("HttpDownload", "check " + check);

   File myFile = new File("/sdcard/folder/" + name);


    myFile.createNewFile();
   OutputStream filoutputStream = new FileOutputStream(myFile);

   filoutputStream.write(b);

   filoutputStream.flush();

   filoutputStream.close();

解决方案

This is some working code I have for downloading a given URL to a given File object. The File object (outputFile) has just been created using new File(path), I haven't called createNewFile or anything.

private static void downloadFile(String url, File outputFile) {
  try {
      URL u = new URL(url);
      URLConnection conn = u.openConnection();
      int contentLength = conn.getContentLength();

      DataInputStream stream = new DataInputStream(u.openStream());

        byte[] buffer = new byte[contentLength];
        stream.readFully(buffer);
        stream.close();

        DataOutputStream fos = new DataOutputStream(new FileOutputStream(outputFile));
        fos.write(buffer);
        fos.flush();
        fos.close();
  } catch(FileNotFoundException e) {
      return; // swallow a 404
  } catch (IOException e) {
      return; // swallow a 404
  }
}

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