Hello,

Here is a sample example to search the database table and fetch the records in grid view using Linq:

protected void btnSearch_Click(object sender, EventArgs e)
    {
        gvAllAdmins.DataSource = GetFilteredRecords(ddlState.SelectedValue, ddlCity.SelectedValue, ddlRoles.SelectedValue);
        gvAllAdmins.DataBind();
        ViewState["sortDirection"] = SortDirection.Ascending;
    }

 public IEnumerable<Login> GetFilteredRecords(string stateId = "-99",
        string cityId = "-99", string roleId = "-99", string sortExpr = "none", string sortDir = "ASC")
    {
        var qry = dc.Logins.Where(x => x.FKRoleId > 1);
        if (stateId != "-99")
        {
            qry = qry.Where(x => x.FKStateID == Convert.ToInt32(stateId));
        }
        if (cityId != "-99")
        {
            qry = qry.Where(x => x.FKCityID == Convert.ToInt32(cityId));
        }
        if (roleId != "-99")
        {
            qry = qry.Where(x => x.FKRoleId == Convert.ToInt32(roleId));
        }
        if (sortExpr != "none")
        {
            if (sortDir == "ASC")
            {
                switch (sortExpr)
                {
                    case "Name": qry = qry.OrderBy(x => x.Name);
                        break;
                    case "emailId": qry = qry.OrderBy(x => x.emailId);
                        break;
                    case "FKStateID": qry = qry.OrderBy(x => x.FKStateID);
                        break;
                    case "IsBlocked": qry = qry.OrderBy(x => x.IsBlocked);
                        break;
                    default:
                        break;
                }
            }
            else if (sortDir == "DESC")
            {
                switch (sortExpr)
                {
                    case "Name": qry = qry.OrderByDescending(x => x.Name);
                        break;
                    case "emailId": qry = qry.OrderByDescending(x => x.emailId);
                        break;
                    case "FKStateID": qry = qry.OrderByDescending(x => x.FKStateID);
                        break;
                    case "IsBlocked": qry = qry.OrderByDescending(x => x.IsBlocked);
                        break;
                    default:
                        break;
                }
            }
        }
        return qry;
    }
For more information on Linq follow the below link:
http://www.bestdotnettraining.com/Online/Training/LINQ/LINQ-to-SQL/109