C# 查看目录文件及文件大小

　　　

　　　private void button1_Click(object sender, EventArgs e)
        {
            BuildTreeView(textBox1.Text);
        }
        long AddDirectory(DirectoryInfo dir, TreeNode tNode)
        {
            FileSystemInfo[] fSIs = dir.GetFileSystemInfos();
            FileSystemInfo fSI;
            int i;
            long directorySize = 0;

            for (i = 0; i < fSIs.Length;i++ )
            {
                fSI = fSIs[i];
                if (fSI.GetType()==typeof(FileInfo))
                {
                    FileInfo fInfo = (FileInfo)fSI;
                    string s = fInfo.Name + FileSizeString(fInfo.Length);
                    TreeNode newTreeNode = new TreeNode(s);
                    tNode.Nodes.Add(newTreeNode);
                    directorySize += fInfo.Length;
                }
                else if (fSI.GetType()==typeof(DirectoryInfo))
                {
                    DirectoryInfo dirInfo = (DirectoryInfo)fSI;
                    TreeNode dirTreeNode = new TreeNode(dirInfo.Name);
                    long dirSize = AddDirectory(dirInfo, dirTreeNode);
                    dirTreeNode.Text += FileSizeString(dirSize);
                    tNode.Nodes.Add(dirTreeNode);
                    directorySize += dirSize;
                }
                else
                {
                    MessageBox.Show("Ooops");
                }
            }
           

            return directorySize;
        }
        string FileSizeString(long fileSize)
        {
            const long OneMB = 1024 * 1024;
            const long OneGB = OneMB * 1024;
            string unit;
            double dispSize;
            if (fileSize<1024)
            {
                unit = "B";
                dispSize = fileSize;
            }
            else if (fileSize<OneMB)
            {
                unit = "KB";
                dispSize = fileSize / 1024;
            }
            else if(fileSize<OneGB)
            {
                unit = "MB";
                dispSize = fileSize / OneMB;
            }
            else
            {
                unit = "GB";
                dispSize = fileSize / OneGB;
            }

            return string.Format("({0,4:F}",dispSize)+unit+")";
        }
        private void BuildTreeView(string dirName)
        {
            DirectoryInfo dirInfo = new DirectoryInfo(dirName);
            TreeNode tNode = new TreeNode(dirName);
            long totalSize = AddDirectory(dirInfo, tNode);

            tNode.Text += FileSizeString(totalSize);
            treeView1.Nodes.Clear();
            treeView1.Nodes.Add(tNode);
        }

        private void button2_Click(object sender, EventArgs e)
        {
            folderBrowser();
        }

        //选择目录对话框
        private void folderBrowser()
        {
            FolderBrowserDialog folderDlg = new FolderBrowserDialog();
            folderDlg.ShowDialog();
            textBox1.Text = folderDlg.SelectedPath;

            BuildTreeView(textBox1.Text);
        }

       
    }