我如何获得单个文件大小？

Question

这是方法:

private void Compressions(string zipFile,string sources)
        {
            try
            {
                string zipFileName = zipFile;
                string source = sources;
                string output = @"c:\temp";
                string programFilesX86 = System.Environment.GetFolderPath(System.Environment.SpecialFolder.ProgramFilesX86) + "\\Diagnostic Tool\\7z.dll";
                if (File.Exists(programFilesX86))
                {
                    SevenZipExtractor.SetLibraryPath(programFilesX86);
                }
                else
                {
                    string path = Path.GetDirectoryName(Assembly.GetEntryAssembly().Location) + "\\7z.dll";
                    SevenZipExtractor.SetLibraryPath(path);
                }
                string programFiles = System.Environment.GetFolderPath(System.Environment.SpecialFolder.ProgramFiles) + "\\Diagnostic Tool\\7z.dll";
                if (File.Exists(programFiles))
                {
                    SevenZipExtractor.SetLibraryPath(programFiles);
                }
                else
                {
                    if (File.Exists(programFilesX86))
                    {
                        SevenZipExtractor.SetLibraryPath(programFilesX86);
                    }
                    else
                    {
                        string path = Path.GetDirectoryName(Assembly.GetEntryAssembly().Location) + "\\7z.dll";
                        SevenZipExtractor.SetLibraryPath(path);
                    }
                }
                SevenZipCompressor compressor = new SevenZipCompressor();
                compressor.ArchiveFormat = OutArchiveFormat.Zip;
                compressor.CompressionMode = CompressionMode.Create;
                compressor.TempFolderPath = System.IO.Path.GetTempPath();
                string t = Path.Combine(output, zipFileName);
                compressor.CompressDirectory(source, t);

                this.explorerWindow = Process.Start("explorer", String.Format("/select,{0}", t));
                this.TopMost = true;
            }
            catch (Exception err)
            {
                Logger.Write("Zip file error: " + err.ToString());
            }
        }

在底部,变量t包含目录和文件名.例如:"c:\ temp\test.txt"我想得到这个文件名大小.

我该怎么做 ？

Answer 1

由于某种原因,静态类File不包含Size(String fileName)方法,而是需要这样做:

Int64 fileSizeInBytes = new FileInfo(fileName).Length;

关于表现:

不要担心new FileInfo分配:

• FileInfo不拥有任何非托管资源(即它不是IDisposable)
• FileInfo构造函数很便宜:构造函数只是获取规范化路径Path.GetFullPath并执行FileIOPermission- 它将规范化路径作为.NET存储String在实例字段中.

大部分工作都在Length属性getter中:它本身就是Win32的包装器GetFileAttributesEx- 所以执行的操作几乎与它是static实用方法时的操作相同.

由于新FileInfo对象是短暂的,这意味着GC将作为第0代对象快速收集它.FileInfo堆上几个字符串(的字段)的开销实际上可以忽略不计.