Question

我想查询服务器以查看日期是否与手机上的日期不同我之前下载过的。如果我已经拥有它，我想不要再次下载图像了。寻找一种方法来获取远程URL文件的日期和时间，而无需再次下载图像。以下代码可以获取所有内容。

       File root = Environment.getExternalStorageDirectory();
   URL u = new URL(url);
   HttpURLConnection c = (HttpURLConnection) u.openConnection();
   c.setRequestMethod("GET");
   c.setDoOutput(true);
   c.connect();
   InputStream in = c.getInputStream();
   Drawable d = Drawable.createFromStream(in, "src name");
   printi("Content length",c.getContentLength());

Answer 1

   File root = Environment.getExternalStorageDirectory();
   URL u = new URL(url);
   HttpURLConnection c = (HttpURLConnection) u.openConnection();
   c.setRequestMethod("HEAD");

   c.connect();
   InputStream in = c.getInputStream();
   long dt=c.getLastModified();  //File Modified Date!!!
   printtime("File Time ",dt);
   c.disconnect();       //close connection  ????

Android：如何从我想下载的图像的URL获取文件日期？

1 个答案: