docs/csharp/snippets/iterators/Generators.cs - main - aprogrammer/dotnet-docs

docs/csharp/snippets/iterators/Generators.cs
126 строк3 KB
Tom Dykstra
update snippet projects (#28379)
24 фев 2022, 19:12
24 фев 2022, 19:12def515f
namespace iterators;

public class Generators
{
    // <GetNumbers>
    public IEnumerable<int> GetSingleDigitNumbers()
    {
        yield return 0;
        yield return 1;
        yield return 2;
        yield return 3;
        yield return 4;
        yield return 5;
        yield return 6;
        yield return 7;
        yield return 8;
        yield return 9;
    }
    // </GetNumbers>

    // <GetNumbersLoop>
    public IEnumerable<int> GetSingleDigitNumbersLoop()
    {
        int index = 0;
        while (index < 10)
            yield return index++;
    }
    // </GetNumbersLoop>

    // <GetMultipleLoops>
    public IEnumerable<int> GetSetsOfNumbers()
    {
        int index = 0;
        while (index < 10)
            yield return index++;

        yield return 50;

        index = 100;
        while (index < 110)
            yield return index++;
    }
    // </GetMultipleLoops>

    // <GetMultipleAsyncLoops>
    public async IAsyncEnumerable<int> GetSetsOfNumbersAsync()
    {
        int index = 0;
        while (index < 10)
            yield return index++;

        await Task.Delay(500);

        yield return 50;

        await Task.Delay(500);

        index = 100;
        while (index < 110)
            yield return index++;
    }
    // </GetMultipleAsyncLoops>

    // <SequenceAndCollection>
    public IEnumerable<int> GetFirstDecile()
    {
        int index = 0;
        while (index < 10)
            yield return index++;

        yield return 50;

        var items = new int[] {100, 101, 102, 103, 104, 105, 106, 107, 108, 109 };
        foreach (var item in items)
            yield return item;
    }
    // </SequenceAndCollection>

    // <ReturnAndYieldReturn>
    public IEnumerable<int> GetSingleDigitOddNumbers(bool getCollection)
    {
        if (getCollection == false)
            return new int[0];
        else
            return IteratorMethod();
    }

    private IEnumerable<int> IteratorMethod()
    {
        int index = 0;
        while (index < 10)
        {
            if (index % 2 == 1)
                yield return index;
            index++;
        }
    }
    // </ReturnAndYieldReturn>
}

public static class Extensions
{
    // <SampleSequence>
    public static IEnumerable<T> Sample<T>(this IEnumerable<T> sourceSequence, int interval)
    {
        int index = 0;
        foreach (T item in sourceSequence)
        {
            if (index++ % interval == 0)
                yield return item;
        }
    }
    // </SampleSequence>

    // <SampleSequenceAsync>
    public static async IAsyncEnumerable<T> Sample<T>(this IAsyncEnumerable<T> sourceSequence, int interval)
    {
        int index = 0;
        await foreach (T item in sourceSequence)
        {
            if (index++ % interval == 0)
                yield return item;
        }
    }
    // </SampleSequenceAsync>
}