Populate a TreeView from a SELF-JOINED table

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Introduction

This very simple example provides a demonstration of how one can populate a TreeView from a self-joined database table. In this example I have used a DataSet containing one DataTable that is populated with virtual XML data.

Core

The SimpleDataSet class provides a DataTable populated with self-joined data. The SimpleTreeView the actual data consumer object.

Sample of how the TreeView is populated

public void CreateNodesOfParent(int iParent,TreeNode pNode) {
            
    DataView dvwData = new DataView(sdsData.Tables[0]);

    dvwData.RowFilter =  "[PARENT] = " + iParent;
    
    foreach(DataRowView Row in dvwData) {
                

        // Call Stack !

        if(pNode == null) {
            TreeNode zNode = this.Nodes.Add(Row["Caption"].ToString());
            CreateNodesOfParent(Int32.Parse(Row["ID"].ToString()),zNode);
        } else {
            TreeNode zNode =  pNode.Nodes.Add(Row["Caption"].ToString());
            CreateNodesOfParent(Int32.Parse(Row["ID"].ToString()),zNode);    
        }
                        
    }            
}        

Sample of how the DataTable is populated

private void CreateDummyData() {
            
    //DataRow objRow;

    // Creating columns

    prvTable = new DataTable("tblTreeView");
    prvTable.Columns.Add("ID",typeof(Int32));
    prvTable.Columns.Add("PARENT",typeof(Int32));
    prvTable.Columns.Add("CAPTION",typeof(String));
            
    // Adding Table to DataSet

    this.Tables.Add(prvTable);
            
                
    prvTable.Rows.Add(new Object[] {1,0,"Countries"});
        prvTable.Rows.Add(new Object[] {2,1,"Netherlands"});
            prvTable.Rows.Add(new Object[] {3,2,"Cities"});            
            prvTable.Rows.Add(new Object[] {4,3,"The Hague"});
            prvTable.Rows.Add(new Object[] {5,3,"Amsterdam"});
            prvTable.Rows.Add(new Object[] {6,3,"Rotterdam"});
    ......
    ......            
}