linq-to-objects

I have an List and I'd like to wrap it into an IQueryable. Is this possible? Paul van Brenk List<int> list = new List<int>() { 1, 2, 3, 4, }; IQueryable<int> query = list.AsQueryable(); If you don't see the AsQueryable() method, add a using statement for System.Linq . Chris Shaffer Use the AsQueryable<T>() extension method. 来源： https://stackoverflow.com/questions/73542/ilistt-to-iqueryablet

In performance point of view what should you use "Nested foreach's" or "lambda/linq queries"? Write the clearest code you can, and then benchmark and profile to discover any performance problems. If you do have performance problems, you can experiment with different code to work out whether it's faster or not (measuring all the time with as realistic data as possible) and then make a judgement call as to whether the improvement in performance is worth the readability hit. A direct foreach approach will be faster than LINQ in many cases. For example, consider: var query = from element in list

var nums = new[]{ 1, 2, 3, 4, 5, 6, 7}; var pairs = /* some linq magic here*/ ; => pairs = { {1, 2}, {3, 4}, {5, 6}, {7, 0} } The elements of pairs should be either two-element lists, or instances of some anonymous class with two fields, something like new {First = 1, Second = 2} . None of the default linq methods can do this lazily and with a single scan. Zipping the sequence with itself does 2 scans and grouping is not entirely lazy. Your best bet is to implement it directly: public static IEnumerable<T[]> Partition<T>(this IEnumerable<T> sequence, int partitionSize) { Contract.Requires