下载文件至本应用程序的file目录或者sdcard - xing2015/Android-Resource GitHub Wiki

感谢作者：风倾清凌 出处：http://www.cnblogs.com/Amandaliu/ 本文版权归作者和博客园共有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利.

一、判断是否有sdcard卡

//判断是否有SD卡 //ture:有SD卡 //false:没有SD卡 public boolean avaiableMedia(){ String status=Environment.getExternalStorageState();

if(status.equals(Environment.MEDIA_MOUNTED)){
    return true;
}
else {
    return false;
}

} 二、下载文件至sdcard卡

if(avaiableMedia()){ HttpClient client = new DefaultHttpClient(); HttpGet get = new HttpGet(url); HttpResponse response; try { response = client.execute(get); HttpEntity entity = response.getEntity(); long length = entity.getContentLength(); InputStream is = entity.getContent(); FileOutputStream fileOutputStream = null; if (is != null) { File file = new File(Environment.getExternalStorageDirectory(),"test.apk"); fileOutputStream = new FileOutputStream(file);

        byte[] buf = new byte[1024];
        int ch = -1;
        int count = 0;
        while ((ch = is.read(buf)) != -1) {
            fileOutputStream.write(buf, 0, ch);
            count += ch;
        }
 
    }
    fileOutputStream.flush();
    if (fileOutputStream != null) {
        fileOutputStream.close();
    }
    if (is != null) {
        is.close();
    }  
} catch (ClientProtocolException e) {
    e.printStackTrace();
} catch (IOException e) {
    e.printStackTrace();
}

}

三、下载文件至本应用程序的数据文件夹

Context 提供了FileOutputStream openFileOutput(String name,int mode)来将数据写入到本应用程序的数据文件（在应用程序下的file目录，一般/data/data/…(应用程序包名)/file）夹。

else{ try { FileOutputStream outStream = this.openFileOutput("test.apk" , Context.MODE_WORLD_READABLE);

HttpClient client = new DefaultHttpClient();
    HttpGet get = new HttpGet(url);
    HttpResponse response;
                  
    response = client.execute(get);
    HttpEntity entity = response.getEntity();
    long length = entity.getContentLength();
    InputStream is = entity.getContent();
    int count = 0;
    if (is != null) {
        byte[] buf = new byte[1024];
        int ch = -1;
         
        while ((ch = is.read(buf)) >0) {
            outStream.write(buf,0,ch);
            count += ch;
            Toast.makeText(getApplicationContext(),"正在下载升级包...",Toast.LENGTH_SHORT).show();
    }
}
             
    outStream.flush();
    if (outStream != null) {
        outStream.close();
    }
    if (is != null) {
        is.close();
    } 

} catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } }