insert update delete data in datagridview without using database in visual basic.net

Imports System.Data.DataTable

Public Class Form2

    Dim table As New DataTable("table")

    Dim index As Integer

    Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        table.Columns.Add("ID", Type.GetType("System.Int32"))

        table.Columns.Add("First name", Type.GetType("System.String"))

        table.Columns.Add("Last name", Type.GetType("System.String"))

        table.Columns.Add("Sum", Type.GetType("System.Int32"))

        DataGridView1.DataSource = table

    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        table.Rows.Add(TextBox1.Text, TextBox2.Text, TextBox3.Text, TextBox4.Text)

        DataGridView1.DataSource = table

    End Sub

   

  

   

    

    Private Sub DataGridView1_CellClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles DataGridView1.CellClick

        index = e.RowIndex

        Dim selectedrow As DataGridViewRow

        selectedrow = DataGridView1.Rows(index)

        TextBox1.Text = selectedrow.Cells(0).Value.ToString

        TextBox2.Text = selectedrow.Cells(1).Value.ToString

        TextBox3.Text = selectedrow.Cells(2).Value.ToString

        TextBox4.Text = selectedrow.Cells(3).Value.ToString

    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click

        Dim newdata As DataGridViewRow

        newdata = DataGridView1.Rows(index)

        newdata.Cells(0).Value = TextBox1.Text

        newdata.Cells(1).Value = TextBox2.Text

        newdata.Cells(2).Value = TextBox3.Text

        newdata.Cells(3).Value = TextBox4.Text

    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

        TextBox1.Text = ""

        TextBox2.Text = ""

        TextBox3.Text = ""

        TextBox4.Text = ""

    End Sub

    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click

        DataGridView1.Rows.RemoveAt(index)

    End Sub

End Class