Add and update record in ASP.Net

Hi makenzi.exc

Please refere the below example.

HTML

<asp:GridView ID="gvVegetables" runat="server" AutoGenerateColumns="false" AllowPaging="true"
            OnPageIndexChanging="OnPageIndexChanging" PageSize="4" OnSelectedIndexChanged="OnSelectedIndexChanged">
            <Columns>
                <asp:BoundField DataField="Id" HeaderText="Id" />
                <asp:BoundField DataField="Name" HeaderText="Name" />
                <asp:BoundField DataField="PricePerKg" HeaderText="PricePerKg" />
                <asp:ButtonField Text="Select" CommandName="Select" />
            </Columns>
        </asp:GridView>
        <br />
        <br />
        <table>
            <tr>
                <td>Id:</td>
                <td>
                    <asp:Label ID="lblId" runat="server"></asp:Label>
                </td>
            </tr>
            <tr>
                <td>Name:</td>
                <td>
                    <asp:TextBox ID="txtName" runat="server"></asp:TextBox></td>
            </tr>
            <tr>
                <td>PricePerKg:</td>
                <td>
                    <asp:TextBox ID="txtPricePerKg" runat="server"></asp:TextBox>
                </td>
            </tr>
            <tr>
                <td></td>
                <td>
                    <asp:Button runat="server" Text="Update" OnClick="OnUpdate" />
                    <asp:Button runat="server" Text="Delete" OnClick="OnDelete" /></td>
            </tr>
        </table>

Database

CREATE TABLE [Vegetables](
	[ID] [int] IDENTITY(1,1) NOT NULL,
	[Name] [varchar](50) NULL,
	[PricePerKg] [varchar](50) NULL,	
 CONSTRAINT [PK_Vegetables] PRIMARY KEY CLUSTERED 
(
	[ID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, OPTIMIZE_FOR_SEQUENTIAL_KEY = OFF) ON [PRIMARY]
) ON [PRIMARY]

Namespace

using System;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Web.UI.WebControls;

Code

#region Events

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindGrid();
    }
}

protected void OnDelete(object sender, EventArgs e)
{
    //Reading the value.
    int id = int.Parse(lblId.Text);
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection sqlConnection = new SqlConnection(constr))
    {
        using (SqlCommand sqlCommand = new SqlCommand("DELETE FROM Vegetables WHERE Id = @Id", sqlConnection))
        {
            //Passing the parameter with value.
            sqlCommand.Parameters.AddWithValue("@Id", id);

            //Opening the sql connection.
            sqlConnection.Open();

            //Executing sql query.
            sqlCommand.ExecuteNonQuery();

            //Closing the sql connection.
        }
        sqlConnection.Close();
    }
    this.BindGrid();
}

protected void OnUpdate(object sender, EventArgs e)
{
    //Reading the values.
    int id = int.Parse(lblId.Text);
    string name = txtName.Text.Trim();
    string pricePerkg = txtPricePerKg.Text.Trim();
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection sqlConnection = new SqlConnection(constr))
    {
        using (SqlCommand sqlCommand = new SqlCommand("UPDATE Vegetables SET Name = @Name, PricePerKg = @PricePerKg WHERE Id = @Id", sqlConnection))
        {
            //Passing the parameters with values.
            sqlCommand.Parameters.AddWithValue("@Id", id);
            sqlCommand.Parameters.AddWithValue("@Name", name);
            sqlCommand.Parameters.AddWithValue("@PricePerKg", pricePerkg);

            //Opening the sql connection.
            sqlConnection.Open();

            //Executing sql query.
            sqlCommand.ExecuteNonQuery();

            //Closing the sql connection.
            sqlConnection.Close();
        }
    }
    this.BindGrid();
}

protected void OnPageIndexChanging(object sender, GridViewPageEventArgs e)
{
    gvVegetables.PageIndex = e.NewPageIndex;
    this.BindGrid();
}

protected void OnSelectedIndexChanged(object seneder, EventArgs e)
{
    //Reading the values.
    int id = int.Parse(gvVegetables.SelectedRow.Cells[0].Text);
    string name = gvVegetables.SelectedRow.Cells[1].Text;
    string pricePerKg = gvVegetables.SelectedRow.Cells[2].Text;
    lblId.Text = id.ToString();
    txtName.Text = name;
      txtPricePerKg.Text = pricePerKg;
}

#endregion

#region Private Methods

/// <summary>
/// Populate of GridView.
/// </summary>
private void BindGrid()
{
    string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection sqlConnection = new SqlConnection(constr))
    {
        using (SqlCommand sqlCommand = new SqlCommand("SELECT Id, Name, PricePerKg FROM Vegetables", sqlConnection))
        {
            using (SqlDataAdapter sqlDataAdapter = new SqlDataAdapter(sqlCommand))
            {
                using (DataTable dtCustomers = new DataTable())
                {
                    sqlDataAdapter.Fill(dtCustomers);
                    gvVegetables.DataSource = dtCustomers;
                    gvVegetables.DataBind();
                }
            }
        }
    }
}

#endregion

Screenshot