Question

我使用下面的代码下载文件并获取其大小下载文件。它给我0值。但是文件下载得很好。

var download = function(uri, filename, callback){
  BASE.request.head(uri, function(err, res, body){
    console.log('content-type:', res.headers['content-type']);
    console.log('content-length:', res.headers['content-length']);

    BASE.request(uri).pipe(BASE.FS.createWriteStream('images/'+filename)).on('close', callback);
      console.log('images/'+filename);
      var stats = BASE.FS.statSync('images/'+filename);
 var fileSizeInBytes = stats["size"];
      console.log(fileSizeInBytes);
 //Convert the file size to megabytes (optional)
 var fileSizeInMegabytes = fileSizeInBytes / 1000000.0;
      console.log(fileSizeInMegabytes);



  });
};


download('https://www.google.com/images/srpr/logo3w.png', 'google.png', function(){
  console.log('done');
});

Answer 1

实际文件大小仅在“关闭”后才可用。事件已经发出。你需要等待管道先完成：

BASE.request(uri).pipe(BASE.FS.createWriteStream('images/'+filename)).on('close', function(err) {
    console.log('images/'+filename);
    var stats = BASE.FS.statSync('images/'+filename);
    var fileSizeInBytes = stats["size"];
    console.log(fileSizeInBytes);
    //Convert the file size to megabytes (optional)
    var fileSizeInMegabytes = fileSizeInBytes / 1000000.0;
    console.log(fileSizeInMegabytes);

    callback(err);
});

如何在node.js中获取图像文件的大小？

1 个答案: