如何使用Linq2Sql将多个数据库列存储到一个数组中

哦,那是。。。美好的这个 DataContext ExecuteReader ,这是一种痛苦(但可以理解,因为它想表现为ORM)。老实说,我很想使用ADO.NET来处理这个表,但是如果您已经将宽表映射到 您应该能够使用常规C#或反射。

Foo foo = new Foo { Id_This = obj.Id_This, Id_That = obj.Id_That,
    Values = new double[] {obj.Value1, obj.Value2, ... } };

如果您有多个表。。。反射,可能通过 Expression :

using System;
using System.Collections.Generic;
using System.Linq.Expressions;
class FooUgly
{
    public int IdThis { get; set; }
    public int IdThat { get; set; }
    public double Value1 { get; set; }
    public double Value2 { get; set; }
    public double Value3 { get; set; }
}
class Foo
{
    public int IdThis { get; set; }
    public int IdThat { get; set; }
    public double[] Values { get; set; }
    public Foo() { }
    internal Foo(FooUgly ugly)
    {
        IdThis = ugly.IdThis;
        IdThat = ugly.IdThat;
        Values = extractor(ugly);
    }
    // re-use this!!!
    static readonly Func<FooUgly, double[]> extractor =
        ValueExtractor<FooUgly, double>.Create("Value", 1, 3);
}
static class Program
{
    static void Main()
    {
        FooUgly ugly = new FooUgly { IdThis = 1, IdThat = 2, Value1 = 3, Value2 = 4, Value3 = 5 };
        Foo foo = new Foo(ugly);
    }
}
static class ValueExtractor<TFrom,TValue>
{
    public static Func<TFrom, TValue[]> Create(string memberPrefix, int start, int end)
    {
        if(end < start) throw new ArgumentOutOfRangeException();
        ParameterExpression param = Expression.Parameter(typeof(TFrom), "source");
        List<Expression> vals = new List<Expression>();
        for(int i = start ; i <= end ; i++) {
            vals.Add(Expression.PropertyOrField(param, memberPrefix + i));
        }
        Expression arr = Expression.NewArrayInit(typeof(TValue), vals);
        return Expression.Lambda<Func<TFrom, TValue[]>>(arr, param).Compile();
    }
}