Linq OrderBy against specific values

Question

Is there a way in Linq to do an OrderBy against a set of values (strings in this case) without knowing the order of the values?

Consider this data:

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Answer 1

I use these. I like the IEnumerable overload for cleanliness, but the priority map version should have better performance on repeated calls.

    public static IEnumerable OrderByStaticList(this IEnumerable items, IReadOnlyDictionary priorityMap)
    {
        return items.OrderBy(x => priorityMap.GetValueOrDefault(x, double.MaxValue));
    }

    public static IEnumerable OrderByStaticList(this IEnumerable items, IEnumerable preferenceOrder)
    {
        int priority = 0;
        var priorityMap = preferenceOrder.ToDictionary(x => x, x => (double) priority++);
        return OrderByStaticList(items, priorityMap);
    }




    [TestMethod]
    public void PriorityMap_DeterminesSort()
    {
        var map = new Dictionary()
        {
            {'A', 1},
            {'B', 7},
            {'C', 3},
            {'D', 42},
            {'E', -1},
        };
        Assert.AreEqual("EACBD", new string("ABCDE".OrderByStaticList(map).ToArray()));
    }

    [TestMethod]
    public void PriorityMapMissingItem_SortsLast()
    {
        var map = new Dictionary()
        {
            {'A', 1},
            {'B', 7},
            {'D', 42},
            {'E', -1},
        };
        Assert.AreEqual("EABDC", new string("ABCDE".OrderByStaticList(map).ToArray()));
    }

    [TestMethod]
    public void OrderedList_DeterminesSort()
    {
        Assert.AreEqual("EACBD", new string("ABCDE".OrderByStaticList("EACBD").ToArray()));
    }

    [TestMethod]
    public void OrderedListMissingItem_SortsLast()
    {
        Assert.AreEqual("EABDC", new string("ABCDE".OrderByStaticList("EABD").ToArray()));
    }