IO-->File and Directory class

The class to process the file and directory mainly include Directory, DirectoryInfo, File,  FileInfo

Directory  : create, move, rename, delete directory with static method . if you will use a directory object many times, you’d better use DirectoryInfo class to create a DreictoryInfo object

DirectoryInfo: be similar with Directory, only differece is that it need to create a object

File: create, move, rename, delete file with static method
FileInfo: be similar with File, only difference is that it uses to create, move, rename, delete file  by Creating FileInfo Object

Samples:
protected DataTable CreateDataSource()
    {
        DataTable dt = new DataTable();
        dt.Columns.Add("filename", typeof(string));
        dt.Columns.Add("size", typeof(int));
        dt.Columns.Add("type", typeof(int));
        dt.Columns.Add("modified", typeof(DateTime));
        //dt.DefaultView.Sort = "type," + dgFiles.GetOrderBy();
        return dt;
    }

DirectoryInfo dirInfo = new DirectoryInfo(“c:\”);
            FileInfo[] info = dirInfo.GetFiles();
            DirectoryInfo[] dirs = dirInfo.GetDirectories();
            DataTable dt = CreateDataSource();// undefined!!!
            DataRow dr;

            foreach (DirectoryInfo dir in dirs)
            {
                dr = dt.NewRow();
                dr["filename"] = dir.Name;
                dr["size"] = "0";
                dr["type"] = "0";
                dt.Rows.Add(dr);
            }

            foreach (FileInfo file in info)
            {
                dr = dt.NewRow();
                dr["filename"] = file.Name;
                dr["size"] = (int)file.Length / 1024;
                dr["type"] = "1";
                dr["modified"] = file.LastWriteTime;
                dt.Rows.Add(dr);
            }