How to insert, update, delete in gridview using c# code

 protected void GridName_DeleteCommand(object source, GridCommandEventArgs e)
     { your code goes here}

protected void GridName_UpdateCommand(object sender, Telerik.Web.UI.GridCommandEventArgs e)
{
if (!(e.Item is GridEditFormInsertItem))
 itemID = (e.Item as GridEditFormItem).GetDataKeyValue("ID").ToString();

 if (!string.IsNullOrEmpty(itemID))       //case edit
        { }
else // case add new

your code goes here

}

 protected void GridName_DeleteCommand(object source, GridCommandEventArgs e)
     { your code goes here}

protected void GridName_UpdateCommand(object sender, Telerik.Web.UI.GridCommandEventArgs e)
{
if (!(e.Item is GridEditFormInsertItem))
 itemID = (e.Item as GridEditFormItem).GetDataKeyValue("ID").ToString();

 if (!string.IsNullOrEmpty(itemID))       //case edit
        { }<pre lang="c#">

onitemcommand="GridName_ItemCommand"
ondeletecommand="GridNameitems_DeleteCommand"
onitemdatabound="GridName_ItemDataBound"

protected void gvPerson_RowEditing(object sender, GridViewEditEventArgs e)
        {
            gvGroupName.EditIndex = e.NewEditIndex;
            gvGroupName.DataBind();
        }

        protected void gvPerson_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
        {
            gvGroupName.EditIndex = -1;
            gvGroupName.DataBind();
        }

        protected void gvPerson_RowUpdating(object sender, GridViewUpdateEventArgs e)
      {

int intId = (int)gvGroupName.DataKeys[e.RowIndex].Value;
        DataRow personRow = dt.Select("groupId=" + intId)[0];

      TextBox txtGname = (TextBox)gvGroupName.Rows[e.RowIndex].Cells[1].Controls[0];
      TextBox txtgroupDes = (TextBox)gvGroupName.Rows[e.RowIndex].Cells[2].Controls[0];
    
      personRow["GName"] = txtGname.Text;
     personRow["groupDes"] = txtgroupDes.Text;


    SqlCommandBuilder cb = new SqlCommandBuilder(da);

     da.Update(dt);

      gvGroupName.EditIndex = -1;

       gvGroupName.DataBind();

}

protected void gvGroup_RowDeleting(object sender, GridViewDeleteEventArgs e)
        {


            
          
            SqlCommand cd = new SqlCommand();
            cd.Connection = con;
            cd.CommandText = "delete from groupName where groupId=@groupId";
            cd.CommandType = System.Data.CommandType.Text;
            cd.Parameters.Add("@groupId", System.Data.SqlDbType.Int).Value = gvGroupName.DataKeys[e.RowIndex].Values["groupId"].ToString();
            con.Open();
            cd.ExecuteNonQuery();
         
            gvGroup();
            DropDownGroup();
            con.Close();

        }