C#

foreach (DataRow row in table.Rows)
                {
                    MainNode = new TreeNode(row.ItemArray[0].ToString());
                    MainNode.Name = row.ItemArray[0].ToString();
                    if (MainNode.Text == "")
                    {
			//Stmts
                       }
                       
                    else
                    {
                        ChildNode = new TreeNode(row.ItemArray[1].ToString());
                        ChildNode.Name = row.ItemArray[1].ToString();
                        if (ChildNode.Text == "")
                        {
                            ChildNode = new TreeNode(row.ItemArray[3].ToString());
                            ChildNode.Name = row.ItemArray[3].ToString();
                            ChildNode.Tag = row.ItemArray[2].ToString();
                            if (!MainNode.Nodes.ContainsKey(ChildNode.Name))
                            {
                                MainNode.Nodes.Add(ChildNode);
                            } }
                        else
                        {
                            SubNode = new TreeNode(row.ItemArray[3].ToString());
                            SubNode.Name = row.ItemArray[3].ToString();
                            SubNode.Tag = row.ItemArray[2].ToString();
                            if (!ChildNode.Nodes.ContainsKey(SubNode.Name))
                            {
                                ChildNode.Nodes.Add(SubNode);
                            } }
                        if (!MainNode.Nodes.ContainsKey(ChildNode.Name))
                        {
                            MainNode.Nodes.Add(ChildNode);
                        }
                        else
                        {
//Here I am unable to understand how to fill child nodes into mainnode
//The below code is wrong 
                            for (int i = 0; i <= MainNode.Nodes.Count; i++)
                            {                               MainNode.Nodes.Add(ChildNode);                                
                            }                   }
                        if (!RootNode.Nodes.ContainsKey(MainNode.Name))
                        {
                            RootNode.Nodes.Add(MainNode);                            
                        }                    }                }            }

<br />
//...<br />
Form1 fmMain=new Form1;<br />
//...Button click<br />
Form2 fmSecond=new Form2();<br />
fm.ShowDialog(fmMain)<br />
//...<br />
private void Form2_Load(object sender, EventArgs e)<br />
{<br />
BindingSource.DataSource = ((Form1)this.Parent).DataSet;<br />
BindingSource.DataMember = "Table";<br />
DataGridView.DataSource=BindingSource;<br />
BindingNavigator.BindingSource=BindingSource;<br />
}<br />

<br />
//...<br />
Form1 fmMain=new Form1;<br />
//...Button click<br />
Form2 fmSecond=new Form2();<br />
fm.ShowDialog(fmMain)<br />
//...<br />
private void Form2_Load(object sender, EventArgs e)<br />
{<br />
DataGridView dt = new DataGridView();<br />
BindingSource.DataSource = ((Form1)this.Parent).DataSet;<br />
BindingSource.DataMember = "Table";<br />
dt.DataSource=BindingSource;<br />
dt.Parent = this;<br />
BindingNavigator.BindingSource=BindingSource;<br />
}<br />

//General Info class
public class General
    {
        private string _name;
        private int _id;

        public General()
        { }
        public General(string Name,int ID)
        {
            _name = Name;
            _id = ID;
        }

        public string GetName
        {
            get { return _name; }           
        }
        public int GetID
        {
            get { return _id; }            
        }
    }