VB.NET, C# รบกวนหน่อยนะคับ ผมอยากรู้เรื่่องเกี่ยวกับ DataSource และ DataGridView ใช้งานยังไงคับ

Private Sub PopulateData()

        '*** BindData From Database **'
        Dim objConn As OleDbConnection
        Dim dtAdapter As OleDbDataAdapter
        Dim dt As New DataTable

        Dim strConnString As String
        strConnString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=mydatabase.mdb"
        objConn = New OleDbConnection(strConnString)
        objConn.Open()

        Dim strSQL As String
        strSQL = "SELECT * FROM customer"

        dtAdapter = New OleDbDataAdapter(strSQL, objConn)
        dtAdapter.Fill(dt)

        dtAdapter = Nothing
        objConn.Close()
        objConn = Nothing

        Me.myDgv.DataSource = dt

        '******************************'
        Me.myDgv.Columns.Clear()

        With myDgv.ColumnHeadersDefaultCellStyle
            .BackColor = Color.Navy
            .ForeColor = Color.White
            .Font = New Font(songsDataGridView.Font, FontStyle.Bold)
        End With

        Dim ColumnTextBox As DataGridViewTextBoxColumn




        '*** Column (Select) ***'
        Dim ColumnCheckBox As New DataGridViewCheckBoxColumn()
        ColumnCheckBox.Width = 30
        ColumnCheckBox.DataPropertyName = "Select"
        Me.myDgv.Columns.Add(ColumnCheckBox)

        '*** Checkbox in Header ***'
        Dim ckBox As New CheckBox()
        Dim rect As Rectangle = myDgv.GetCellDisplayRectangle(0, -1, True)
        ckBox.Size = New Size(18, 18)
        rect.X = rect.Location.X + (rect.Width / 4)
        ckBox.Location = rect.Location
        AddHandler ckBox.CheckedChanged, New EventHandler(AddressOf ckBox_CheckedChanged)
        Me.myDgv.Controls.Add(ckBox)

        myDgv.Columns(0).Frozen = False

        '*** Column (CustomerID) ***'
        ColumnTextBox = New DataGridViewTextBoxColumn()
        ColumnTextBox.DataPropertyName = "CustomerID"
        ColumnTextBox.HeaderText = "CustomerID"
        ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter
        ColumnTextBox.Width = 100
        Me.myDgv.Columns.Add(ColumnTextBox)

        '*** Column (Name) ***'
        ColumnTextBox = New DataGridViewTextBoxColumn()
        ColumnTextBox.DataPropertyName = "Name"
        ColumnTextBox.HeaderText = "Name"
        ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter
        ColumnTextBox.Width = 100
        Me.myDgv.Columns.Add(ColumnTextBox)

        '*** Column (Email) ***'
        ColumnTextBox = New DataGridViewTextBoxColumn()
        ColumnTextBox.DataPropertyName = "Email"
        ColumnTextBox.HeaderText = "Email"
        ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter
        ColumnTextBox.Width = 100
        Me.myDgv.Columns.Add(ColumnTextBox)

        '*** Column (CountryCode) ***'
        ColumnTextBox = New DataGridViewTextBoxColumn()
        ColumnTextBox.DataPropertyName = "CountryCode"
        ColumnTextBox.HeaderText = "CountryCode"
        ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter
        ColumnTextBox.Width = 100
        Me.myDgv.Columns.Add(ColumnTextBox)

        '*** Column (Budget) ***'
        ColumnTextBox = New DataGridViewTextBoxColumn()
        ColumnTextBox.DataPropertyName = "Budget"
        ColumnTextBox.HeaderText = "Budget"
        ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter
        ColumnTextBox.Width = 100
        Me.myDgv.Columns.Add(ColumnTextBox)

        '*** Column (Used) ***'
        ColumnTextBox = New DataGridViewTextBoxColumn()
        ColumnTextBox.DataPropertyName = "Used"
        ColumnTextBox.HeaderText = "Used"
        ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter
        ColumnTextBox.Width = 100
        Me.myDgv.Columns.Add(ColumnTextBox)

    End Sub

private void PopulateData()
{
	//*** BindData From Database **'
	OleDbConnection objConn = default(OleDbConnection);
	OleDbDataAdapter dtAdapter = default(OleDbDataAdapter);
	DataTable dt = new DataTable();

	string strConnString = null;
	strConnString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=mydatabase.mdb";
	objConn = new OleDbConnection(strConnString);
	objConn.Open();

	string strSQL = null;
	strSQL = "SELECT * FROM customer";

	dtAdapter = new OleDbDataAdapter(strSQL, objConn);
	dtAdapter.Fill(dt);

	dtAdapter = null;
	objConn.Close();
	objConn = null;

	this.myDgv.DataSource = dt;

	//******************************'
	this.myDgv.Columns.Clear();

	var _with1 = myDgv.ColumnHeadersDefaultCellStyle;
	_with1.BackColor = Color.Navy;
	_with1.ForeColor = Color.White;
	_with1.Font = new Font(songsDataGridView.Font, FontStyle.Bold);

	DataGridViewTextBoxColumn ColumnTextBox = default(DataGridViewTextBoxColumn);




	//*** Column (Select) ***'
	DataGridViewCheckBoxColumn ColumnCheckBox = new DataGridViewCheckBoxColumn();
	ColumnCheckBox.Width = 30;
	ColumnCheckBox.DataPropertyName = "Select";
	this.myDgv.Columns.Add(ColumnCheckBox);

	//*** Checkbox in Header ***'
	CheckBox ckBox = new CheckBox();
	Rectangle rect = myDgv.GetCellDisplayRectangle(0, -1, true);
	ckBox.Size = new Size(18, 18);
	rect.X = rect.Location.X + (rect.Width / 4);
	ckBox.Location = rect.Location;
	ckBox.CheckedChanged += new EventHandler(ckBox_CheckedChanged);
	this.myDgv.Controls.Add(ckBox);

	myDgv.Columns(0).Frozen = false;

	//*** Column (CustomerID) ***'
	ColumnTextBox = new DataGridViewTextBoxColumn();
	ColumnTextBox.DataPropertyName = "CustomerID";
	ColumnTextBox.HeaderText = "CustomerID";
	ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter;
	ColumnTextBox.Width = 100;
	this.myDgv.Columns.Add(ColumnTextBox);

	//*** Column (Name) ***'
	ColumnTextBox = new DataGridViewTextBoxColumn();
	ColumnTextBox.DataPropertyName = "Name";
	ColumnTextBox.HeaderText = "Name";
	ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter;
	ColumnTextBox.Width = 100;
	this.myDgv.Columns.Add(ColumnTextBox);

	//*** Column (Email) ***'
	ColumnTextBox = new DataGridViewTextBoxColumn();
	ColumnTextBox.DataPropertyName = "Email";
	ColumnTextBox.HeaderText = "Email";
	ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter;
	ColumnTextBox.Width = 100;
	this.myDgv.Columns.Add(ColumnTextBox);

	//*** Column (CountryCode) ***'
	ColumnTextBox = new DataGridViewTextBoxColumn();
	ColumnTextBox.DataPropertyName = "CountryCode";
	ColumnTextBox.HeaderText = "CountryCode";
	ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter;
	ColumnTextBox.Width = 100;
	this.myDgv.Columns.Add(ColumnTextBox);

	//*** Column (Budget) ***'
	ColumnTextBox = new DataGridViewTextBoxColumn();
	ColumnTextBox.DataPropertyName = "Budget";
	ColumnTextBox.HeaderText = "Budget";
	ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter;
	ColumnTextBox.Width = 100;
	this.myDgv.Columns.Add(ColumnTextBox);

	//*** Column (Used) ***'
	ColumnTextBox = new DataGridViewTextBoxColumn();
	ColumnTextBox.DataPropertyName = "Used";
	ColumnTextBox.HeaderText = "Used";
	ColumnTextBox.HeaderCell.Style.Alignment = DataGridViewContentAlignment.MiddleCenter;
	ColumnTextBox.Width = 100;
	this.myDgv.Columns.Add(ColumnTextBox);

}