parent /child relationship with multiple key columns

hi Steven 

If you mean self-references in radgridview

You can use this code


        private static DataTable CreateDataSource()
        {
            DataTable dataSource = new DataTable("fileSystem");
            dataSource.Columns.Add("ID", typeof(int));
            dataSource.Columns.Add("ParentID", typeof(int));
            dataSource.Columns.Add("Name", typeof(string));
            dataSource.Columns.Add("Date", typeof(DateTime));
            dataSource.Columns.Add("Type", typeof(string));
            dataSource.Columns.Add("Size", typeof(int));

            dataSource.Rows.Add(1, null, "Program Files", DateTime.Now.AddDays(-100), "Folder", 5120);
            dataSource.Rows.Add(2, 1, "Visual Studio 2010", DateTime.Now.AddDays(-100), "Folder", 3220);
            dataSource.Rows.Add(3, 2, "bin", DateTime.Now.AddDays(-100), "Folder", 3220);
            dataSource.Rows.Add(4, 2, "READEME.txt", DateTime.Now.AddDays(-100), "Text Document", 3);

            dataSource.Rows.Add(5, 1, "Telerik RadControls", DateTime.Now.AddDays(-10), "Folder", 3120);
            dataSource.Rows.Add(6, 5, "Telerik UI for Winforms", DateTime.Now.AddDays(-10), "Folder", 101);
            dataSource.Rows.Add(7, 5, "Telerik UI for Silverlight", DateTime.Now.AddDays(-10), "Folder", 123);
            dataSource.Rows.Add(8, 5, "Telerik UI for WPF", DateTime.Now.AddDays(-10), "Folder", 221);
            dataSource.Rows.Add(9, 5, "Telerik UI for ASP.NET AJAX", DateTime.Now.AddDays(-10), "Folder", 121);

            dataSource.Rows.Add(10, 1, "Microsoft Office 2010", DateTime.Now.AddDays(-120), "Folder", 1230);
            dataSource.Rows.Add(11, 10, "Microsoft Word 2010", DateTime.Now.AddDays(-120), "Folder", 1230);
            dataSource.Rows.Add(12, 10, "Microsoft Excel 2010", DateTime.Now.AddDays(-120), "Folder", 1230);
            dataSource.Rows.Add(13, 10, "Microsoft Powerpoint 2010", DateTime.Now.AddDays(-120), "Folder", 1230);

            dataSource.Rows.Add(14, 1, "Debug Diagnostic Tools v1.0", DateTime.Now.AddDays(-400), "Folder", 2120);
            dataSource.Rows.Add(15, 1, "Designer's 3D Tools", DateTime.Now.AddDays(-500), "Folder", 1120);
            dataSource.Rows.Add(16, 1, "Communication", DateTime.Now.AddDays(-700), "Folder", 120);

            dataSource.Rows.Add(17, null, "My Documents", DateTime.Now.AddDays(-200), "Folder", 1024);
            dataSource.Rows.Add(18, 17, "Salaries.xlsx", DateTime.Now.AddDays(-200), "Excel File", 1);
            dataSource.Rows.Add(19, 17, "RecessionAnalysis.xlsx", DateTime.Now.AddDays(-200), "Excel File", 1);

        

            dataSource.Rows.Add(33, null, "Boot.ini", DateTime.Now.AddDays(-10), "INI File", 0);

            return dataSource;
        }

        protected override void OnLoad(EventArgs e)
        {
 
            this.radGridView1.MasterTemplate.AutoSizeColumnsMode = GridViewAutoSizeColumnsMode.Fill;
            this.radGridView1.DataSource = CreateDataSource();
            this.radGridView1.Relations.AddSelfReference(this.radGridView1.MasterTemplate, "ID", "ParentID");

            this.radGridView1.Columns["ID"].IsVisible = false;
            this.radGridView1.Columns["ParentID"].IsVisible = false;
            this.radGridView1.Columns["Size"].FormatString = "{0} MB";

        }

 and You can find this code in Demo Application - Telerik UI for WinForms , In case installed on your computer