Dapper: How to return selected columns?

Question

Dapper: How to return selected columns?

dapper

Question

public List<Customer> getCustomer() 
{
    using (IDbConnection con=DapperConnection())
    {
        string sql = "Select * from Customer";
        return con.Query<Customer>(sql).Select(x => new { x.Id, x.LastName })
                    .ToList();
    }
}

class Customer 
{
    public string Id { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set;}
}

Does anyone know how to return specific columns using dapper? What I am trying to achieve is to return just the Id and LastName as List so that I can bind them to my controls.

Dikong Prigm

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JFM · Accepted Answer · 12/23/2016 7:28:20 AM

Unsure exactly what you mean but surely you should return the customer object instead of an anonymous type, or at least make a smaller version of the customer object to be used by the controls

    public List<Customer> getCustomers()
    {
        using (IDbConnection con = DapperConnection())
        {
            string sql = "Select * from Customer";
            return con.Query<Customer>(sql).ToList();
        }
    }

Or if you dont like the overhead of returning the full customer object

    public List<CustomerBase> getCustomers()
    {
        using (IDbConnection con = DapperConnection())
        {
            string sql = "Select * from Customer";
            return con.Query<CustomerBase>(sql).ToList();
        }
    }

    public class CustomerBase
    {
        public string Id { get; set; }
        public string LastName { get; set; }
    }

    public class Customer: CustomerBase
    {
        public string FirstName { get; set; }
        //Other props...
    }

Dapper: How to return selected columns?

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