Question

如何创建ValueTuple的列表，其中包括八个以上的值：

(int Id, string FirstName, string LastName, int Vek, int City, int Zip, int Country, int Street, int Firm, int Age, int Bank, bool IsActive) person =
   (1, "Bill", "Gates", 4, 5, 6, 7, 8, 9, 10, 11, true);

Answer 1

你不能

ValueTuple Struct

尽管有多种方法可以将元组戳入元组和其他类型，但是您必须创建自己的元组...

但是，在所有事物都是平等的情况下，听起来像是要创建一个类，并在所有类型的命名荣耀中拥有世界上最好的

The source for all Tupley goodness found here

public class Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> : IStructuralEquatable, IStructuralComparable, IComparable, ITupleInternal, ITuple {

    private readonly T1 m_Item1;
    private readonly T2 m_Item2;
    private readonly T3 m_Item3;
    private readonly T4 m_Item4;
    private readonly T5 m_Item5;
    private readonly T6 m_Item6;
    private readonly T7 m_Item7;
    private readonly TRest m_Rest;

    public T1 Item1 { get { return m_Item1; } }
    public T2 Item2 { get { return m_Item2; } }
    public T3 Item3 { get { return m_Item3; } }
    public T4 Item4 { get { return m_Item4; } }
    public T5 Item5 { get { return m_Item5; } }
    public T6 Item6 { get { return m_Item6; } }
    public T7 Item7 { get { return m_Item7; } }
    public TRest Rest { get { return m_Rest; } }

    public Tuple(T1 item1, T2 item2, T3 item3, T4 item4, T5 item5, T6 item6, T7 item7, TRest rest) {
        if (!(rest is ITupleInternal)) {
            throw new ArgumentException(Environment.GetResourceString("ArgumentException_TupleLastArgumentNotATuple"));
        }

        m_Item1 = item1;
        m_Item2 = item2;
        m_Item3 = item3;
        m_Item4 = item4;
        m_Item5 = item5;
        m_Item6 = item6;
        m_Item7 = item7;
        m_Rest = rest;
    }

    public override Boolean Equals(Object obj) {
        return ((IStructuralEquatable) this).Equals(obj, EqualityComparer<Object>.Default);;
    }

    Boolean IStructuralEquatable.Equals(Object other, IEqualityComparer comparer) {
        if (other == null) return false;

        Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> objTuple = other as Tuple<T1, T2, T3, T4, T5, T6, T7, TRest>;

        if (objTuple == null) {
            return false;
        }

        return comparer.Equals(m_Item1, objTuple.m_Item1) && comparer.Equals(m_Item2, objTuple.m_Item2) && comparer.Equals(m_Item3, objTuple.m_Item3) && comparer.Equals(m_Item4, objTuple.m_Item4) && comparer.Equals(m_Item5, objTuple.m_Item5) && comparer.Equals(m_Item6, objTuple.m_Item6) && comparer.Equals(m_Item7, objTuple.m_Item7) && comparer.Equals(m_Rest, objTuple.m_Rest);
    }

    Int32 IComparable.CompareTo(Object obj) {
        return ((IStructuralComparable) this).CompareTo(obj, Comparer<Object>.Default);
    }

    Int32 IStructuralComparable.CompareTo(Object other, IComparer comparer) {
        if (other == null) return 1;

        Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> objTuple = other as Tuple<T1, T2, T3, T4, T5, T6, T7, TRest>;

        if (objTuple == null) {
            throw new ArgumentException(Environment.GetResourceString("ArgumentException_TupleIncorrectType", this.GetType().ToString()), "other");
        }

        int c = 0;

        c = comparer.Compare(m_Item1, objTuple.m_Item1);

        if (c != 0) return c;

        c = comparer.Compare(m_Item2, objTuple.m_Item2);

        if (c != 0) return c;

        c = comparer.Compare(m_Item3, objTuple.m_Item3);

        if (c != 0) return c;

        c = comparer.Compare(m_Item4, objTuple.m_Item4);

        if (c != 0) return c;

        c = comparer.Compare(m_Item5, objTuple.m_Item5);

        if (c != 0) return c;

        c = comparer.Compare(m_Item6, objTuple.m_Item6);

        if (c != 0) return c;

        c = comparer.Compare(m_Item7, objTuple.m_Item7);

        if (c != 0) return c;

        return comparer.Compare(m_Rest, objTuple.m_Rest);
    }

    public override int GetHashCode() {
        return ((IStructuralEquatable) this).GetHashCode(EqualityComparer<Object>.Default);
    }

    Int32 IStructuralEquatable.GetHashCode(IEqualityComparer comparer) {
        // We want to have a limited hash in this case.  We'll use the last 8 elements of the tuple
        ITupleInternal t = (ITupleInternal) m_Rest;
        if(t.Length >= 8) { return t.GetHashCode(comparer); }

        // In this case, the rest memeber has less than 8 elements so we need to combine some our elements with the elements in rest
        int k = 8 - t.Length;
        switch(k) {
            case 1:
            return Tuple.CombineHashCodes(comparer.GetHashCode(m_Item7), t.GetHashCode(comparer));
            case 2:
            return Tuple.CombineHashCodes(comparer.GetHashCode(m_Item6), comparer.GetHashCode(m_Item7), t.GetHashCode(comparer));
            case 3:
            return Tuple.CombineHashCodes(comparer.GetHashCode(m_Item5), comparer.GetHashCode(m_Item6), comparer.GetHashCode(m_Item7), t.GetHashCode(comparer));
            case 4:
            return Tuple.CombineHashCodes(comparer.GetHashCode(m_Item4), comparer.GetHashCode(m_Item5), comparer.GetHashCode(m_Item6), comparer.GetHashCode(m_Item7), t.GetHashCode(comparer));
            case 5:
            return Tuple.CombineHashCodes(comparer.GetHashCode(m_Item3), comparer.GetHashCode(m_Item4), comparer.GetHashCode(m_Item5), comparer.GetHashCode(m_Item6), comparer.GetHashCode(m_Item7), t.GetHashCode(comparer));
            case 6:
            return Tuple.CombineHashCodes(comparer.GetHashCode(m_Item2), comparer.GetHashCode(m_Item3), comparer.GetHashCode(m_Item4), comparer.GetHashCode(m_Item5), comparer.GetHashCode(m_Item6), comparer.GetHashCode(m_Item7), t.GetHashCode(comparer));
            case 7:
            return Tuple.CombineHashCodes(comparer.GetHashCode(m_Item1), comparer.GetHashCode(m_Item2), comparer.GetHashCode(m_Item3), comparer.GetHashCode(m_Item4), comparer.GetHashCode(m_Item5), comparer.GetHashCode(m_Item6), comparer.GetHashCode(m_Item7), t.GetHashCode(comparer));
        }
        Contract.Assert(false, "Missed all cases for computing Tuple hash code");
        return -1;
    }

    Int32 ITupleInternal.GetHashCode(IEqualityComparer comparer) {
        return ((IStructuralEquatable) this).GetHashCode(comparer);
    }
    public override string ToString() {
        StringBuilder sb = new StringBuilder();
        sb.Append("(");
        return ((ITupleInternal)this).ToString(sb);
    }

    string ITupleInternal.ToString(StringBuilder sb) {
        sb.Append(m_Item1);
        sb.Append(", ");
        sb.Append(m_Item2);
        sb.Append(", ");
        sb.Append(m_Item3);
        sb.Append(", ");
        sb.Append(m_Item4);
        sb.Append(", ");
        sb.Append(m_Item5);
        sb.Append(", ");
        sb.Append(m_Item6);
        sb.Append(", ");
        sb.Append(m_Item7);
        sb.Append(", ");
        return ((ITupleInternal)m_Rest).ToString(sb);
    }

    /// <summary>
    /// The number of positions in this data structure.
    /// </summary>
    int ITuple.Length
    {
        get
        {
            return 7 + ((ITupleInternal)Rest).Length;
        }
    }

    /// <summary>
    /// Get the element at position <param name="index"/>.
    /// </summary>
    object ITuple.this[int index]
    {
        get
        {
            switch (index)
            {
                case 0:
                    return Item1;
                case 1:
                    return Item2;
                case 2:
                    return Item3;
                case 3:
                    return Item4;
                case 4:
                    return Item5;
                case 5:
                    return Item6;
                case 6:
                    return Item7;
            }

            return ((ITupleInternal)Rest)[index - 7];
        }
    }
}

DavidG的评论

编译器将设置Rest参数成为另一个ValueTuple ...提供的图像

ValueTuple(T1, T2, T3, T4, T5, T6, T7, TRest) Constructor

TRest任何值元组类型的实例，其中包含   值的元组剩余元素。

如何创建超过八个值的ValueTuple列表？

1 个答案: