Binding to Self Referencing Data

Binding RadTreeView to self referencing data differs from binding to related 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.

All parent identifiers must be positive numbers.

Minimal example

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


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;
}

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:

treeview-data-binding-binding-to-self-referencing-data 001

See Also

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