# Binding to Self Referencing Data

Binding RadTreeView to self referencing data differs from [binding to related data](https://www.telerik.com/products/winforms/documentation/controls/treeview/data-binding/binding-to-object-relational-data) in that RadTreeView is bound to a single list instead of multiple related lists.

In order to set the parent-child relation between the records of the data source, we should set the **ParentMember** and **ChildMember** properties to the respective fields in the data source. If the parent `ID` for a record does not have a respective value in the child `ID` field of the records, then that record is considered to have no parents.

> important All parent identifiers must be positive numbers.

## Minimal example

The following example demonstrates how to bind RadTreeView to a self referencing DataTable.

```C#
public BindingToSelfRefData()
{
    InitializeComponent();
    
    this.radTreeView1.DisplayMember = "name";
    this.radTreeView1.ParentMember = "pid";
    this.radTreeView1.ChildMember = "id";
    this.radTreeView1.DataSource = this.GetSampleData();
}

private DataTable GetSampleData()
{
    DataTable dt = new DataTable();
    
    DataColumn dc = new DataColumn();
    dc.ColumnName = "id";
    dc.DataType = typeof(int);
    dt.Columns.Add(dc);
    
    DataColumn dc1 = new DataColumn();
    dc1.ColumnName = "name";
    dc1.DataType = typeof(string);
    dt.Columns.Add(dc1);
    
    DataColumn dc2 = new DataColumn();
    dc2.ColumnName = "pid";
    dc2.DataType = typeof(int);
    dt.Columns.Add(dc2);
    
    DataRow dr = dt.NewRow();
    dr[0] = 0;
    dr[1] = "My Computer";
    dr[2] = DBNull.Value;
    dt.Rows.Add(dr);
    
    dr = dt.NewRow();
    dr[0] = 1;
    dr[1] = @"C:\";
    dr[2] = 0;
    dt.Rows.Add(dr);
    
    dr = dt.NewRow();
    dr[0] = 2;
    dr[1] = @"D:\";
    dr[2] = 0;
    dt.Rows.Add(dr);
    
    dr = dt.NewRow();
    dr[0] = 3;
    dr[1] = "Program Files";
    dr[2] = 1;
    dt.Rows.Add(dr);
    
    dr = dt.NewRow();
    dr[0] = 4;
    dr[1] = "Microsoft";
    dr[2] = 3;
    dt.Rows.Add(dr);
    
    dr = dt.NewRow();
    dr[0] = 5;
    dr[1] = "Telerik";
    dr[2] = 3;
    dt.Rows.Add(dr);
    
    dr = dt.NewRow();
    dr[0] = 6;
    dr[1] = "WINDOWS";
    dr[2] = 1;
    dt.Rows.Add(dr);
    
    return dt;
}

```

```VB.NET
Public Sub New()
    InitializeComponent()

    Me.RadTreeView1.DisplayMember = "name"
    Me.RadTreeView1.ParentMember = "pid"
    Me.RadTreeView1.ChildMember = "id"
    Me.RadTreeView1.DataSource = Me.GetSampleData()
End Sub

Private Function GetSampleData() As DataTable
    Dim dt As New DataTable()

    Dim dc As New DataColumn()
    dc.ColumnName = "id"
    dc.DataType = GetType(Integer)
    dt.Columns.Add(dc)

    Dim dc1 As New DataColumn()
    dc1.ColumnName = "name"
    dc1.DataType = GetType(String)
    dt.Columns.Add(dc1)

    Dim dc2 As New DataColumn()
    dc2.ColumnName = "pid"
    dc2.DataType = GetType(Integer)
    dt.Columns.Add(dc2)

    Dim dr As DataRow = dt.NewRow()
    dr(0) = 0
    dr(1) = "My Computer"
    dr(2) = DBNull.Value
    dt.Rows.Add(dr)

    dr = dt.NewRow()
    dr(0) = 1
    dr(1) = "C:\"
    dr(2) = 0
    dt.Rows.Add(dr)

    dr = dt.NewRow()
    dr(0) = 2
    dr(1) = "D:\"
    dr(2) = 0
    dt.Rows.Add(dr)

    dr = dt.NewRow()
    dr(0) = 3
    dr(1) = "Program Files"
    dr(2) = 1
    dt.Rows.Add(dr)

    dr = dt.NewRow()
    dr(0) = 4
    dr(1) = "Microsoft"
    dr(2) = 3
    dt.Rows.Add(dr)

    dr = dt.NewRow()
    dr(0) = 5
    dr(1) = "Telerik"
    dr(2) = 3
    dt.Rows.Add(dr)

    dr = dt.NewRow()
    dr(0) = 6
    dr(1) = "WINDOWS"
    dr(2) = 1
    dt.Rows.Add(dr)

    Return dt
End Function
```

As a result we get the hierarchy of nodes shown below:

![WinForms RadTreeView Self Reference Hierarchy](https://www.telerik.com/products/winforms/documentation/assets/537c92c53e2f20944990f91b1bb3c929/treeview-data-binding-binding-to-self-referencing-data001.png)

## See Also

* [Binding to Database Data](https://www.telerik.com/products/winforms/documentation/controls/treeview/data-binding/binding-to-database-data)

* [Binding to Object-relational Data](https://www.telerik.com/products/winforms/documentation/controls/treeview/data-binding/binding-to-object-relational-data)

* [Binding to XML Data](https://www.telerik.com/products/winforms/documentation/controls/treeview/data-binding/binding-to-xml-data)

* [Data Binding](https://www.telerik.com/products/winforms/documentation/controls/treeview/data-binding/overview)

* [Binding CheckBoxes](https://www.telerik.com/products/winforms/documentation/controls/treeview/data-binding/databinding-checkboxes)

* [Serialize/Deserialize to XML](https://www.telerik.com/products/winforms/documentation/controls/treeview/data-binding/deserialize-to-xml)