This is an example of editing in DataGrid and Default Paging


Html Design Code : -

<asp:DataGrid id="DataGrid1" DataKeyField="id" runat="server" Height="224px" AutoGenerateColumns="False" PageSize="5" AllowPaging="True">
<Columns>
<asp:BoundColumn Visible="False" DataField="id"
HeaderText="Category Id"></asp:BoundColumn>
<asp:TemplateColumn HeaderText="Category">
<ItemTemplate>
<asp:Label id=lblName text='<%# DataBinder.Eval(Container.DataItem,"name")%>' Runat="server">
</asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:TextBox id=txtEdit Runat="server" Text='<%# DataBinder.Eval(Container.DataItem,"name")%>'>
</asp:TextBox>
</EditItemTemplate>
</asp:TemplateColumn>
<asp:EditCommandColumn ButtonType="LinkButton" UpdateText="Update" HeaderText="Edit" CancelText="Cancel"
                        EditText="Edit"></asp:EditCommandColumn>
    </Columns>
    </asp:DataGrid>

Code (EditInDataGrid.aspx.cs) :

private void Page_Load(object sender, System.EventArgs e)
        {
            // Put user code to initialize the page here
            if(!IsPostBack)
            {

                BindGrid();
            }
        }
private void DataGrid1_EditCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
        {
            DataGrid1.EditItemIndex = e.Item.ItemIndex;
            BindGrid();

        }
private void BindGrid()
        {
            SqlDataAdapter da = new SqlDataAdapter("select id,name from category",con);
            DataSet objDS = new DataSet();
            try
            {
                da.Fill(objDS,"Cat");
                if(objDS.Tables[0].Rows.Count != 0)
                {
                    DataGrid1.DataSource = objDS;
                    DataGrid1.DataBind();
                }
                else
                {
                    DataGrid1.DataSource = null;
                    DataGrid1.DataBind();

                    Response.Write("No record found.");
                }
            }
            catch(Exception ex)
            {
                throw ex;
            }
        }

private void DataGrid1_UpdateCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
        {
            try
            {
                string strCatName = ((TextBox)e.Item.FindControl("txtEdit")).Text;
                string strId = DataGrid1.DataKeys[e.Item.ItemIndex].ToString();
                SqlCommand com = new SqlCommand("update category set name ='"+strCatName+"' where id = "+strId,con);
                con.Open();
                com.ExecuteNonQuery();
                DataGrid1.EditItemIndex = -1;
                BindGrid();
            }
            catch(Exception ex)
            {
                throw ex;
            }
        }

        private void DataGrid1_CancelCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e)
        {
            DataGrid1.EditItemIndex = -1;
            BindGrid();
        }

        private void DataGrid1_PageIndexChanged(object source, System.Web.UI.WebControls.DataGridPageChangedEvent Args e)
        {
            DataGrid1.CurrentPageIndex = e.NewPageIndex;
            BindGrid();