Question

我在磁盘上有很多文件需要读取和反序列化。如果我尝试使用多个任务的流读取器访问这些文件，我会得到以下异常：

var storage =   multer.diskStorage({
      destination: function (req, file, callback) {
        callback(null, '../uploads');
      },
      filename: function (req, file, callback) {
        callback(null, file.originalname + '-' + new Date().toISOString().replace(/T/, ' ').replace(/\..+/, ''));

      }
    });


var video   =   multer.diskStorage({
      destination: function (req, file, callback) {
        callback(null, '../attachuploads');
      },
      filename: function (req, file, callback) {
        callback(null, file.originalname + '-' + new Date().toISOString().replace(/T/, ' ').replace(/\..+/, ''));

      }
    });

var upload = multer({ storage : storage, video : video });

/* Create Course */
router.post('/create', upload.any(),function(req, res, file) {

        var uploadpath =dirname+'/uploads/'+ req.files[0].originalname+ '-' + new Date().toISOString().replace(/T/, ' ').replace(/\..+/, '');
        var videopath =dirname+'/attachuploads/'+ req.files[0].originalname+ '-' + new Date().toISOString().replace(/T/, ' ').replace(/\..+/, '');
        var courses = new Course({ 
            course_Name: req.body.coursename,
            course_Code: req.body.coursecode,
            course_Title: req.body.coursetitle,
            course_Author: req.body.courseauthor,
            course_Discription: req.body.coursediscription,
            course_Attachments: uploadpath,
            course_Video: videopath,
            course_Urlpath: req.body.courseurlpath,
            course_StartingDate: req.body.coursestartingdate,
            course_EndingDate: req.body.courseendingdate 
       });

        // save the sample course
        courses.save(function(err) {
            if (err) {throw err;}
            res.json({ success: true });

    });
});

以下是代码：

System.ObjectDisposedException: Cannot access a disposed object
System.Runtime.InteropServices.SafeHandle.DangerousReleaseInternal(bool dispose)SafeHandle.cs:193
System.Runtime.InteropServices.SafeHandle.DangerousRelease()SafeHandle.cs:142
System.IO.FileStream.Dispose(bool disposing)FileStream.cs:913
System.IO.IsolatedStorage.IsolatedStorageFileStream.Dispose(bool disposing)IsolatedStorageFileStream.cs:250
System.IO.Stream.Close()stream.cs:248
 System.IO.StreamReader.Dispose(bool disposing)streamreader.cs:296
System.IO.TextReader.Dispose()textreader.cs:78
System.IO.TextReader.Dispose()(wrapper remoting-invoke-with-check)
.FileServices.StreamReaderWrapper.Dispose()
.FileServices.IsolatedSerializer.<DeserializeAsync>d__9<T>.MoveNext()

我在这里做错了什么？

public async Task<T> DeserializeAsync<T>(string path)
{
    T result = default(T);
    if (!_fileRepository.FileManager.FileExists(path)) { return result; }

    using (var streamReader = _streamReader.GetNew(_fileRepository.FileManager.OpenFile(
            path, FileMode.Open, FileAccess.Read, FileShare.Read)))
    {
        var contents = await streamReader.ReadToEndAsync();
        result = _jsonSerializer.DeserializeFromString<T>(contents, Encoding.UTF8);
        streamReader.Dispose();
    }
    return result;
}

Answer 1

您正在拨打Dispose两次。退出代码块后，using语句将自动处理您的streamReader变量。但你也明确地呼吁streamReader.Dispose();

另外，你的StreamReaderWrapper.GetNew()应该只返回一个新的包装器实例，否则线程会互相踩到脚趾

Answer 2

我认为你无法访问＆＃34; getNew＆＃34;功能，因为你已经处理了对象..

来自您的代码：

使用（var streamReader = _streamReader.GetNew（_fileRepository.FileManager.OpenFile（

）

谁＆＃34; _streamReader＆＃34;？包装器或包装读取器的实例？

从多个任务访问相同的文件

2 个答案: