docs/csharp/linq/snippets/HowToExtend/Program.cs - main - aprogrammer/dotnet-docs

docs/csharp/linq/snippets/HowToExtend/Program.cs

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Bill Wagner

Finish freshness update / reorg on LINQ content (#40437)

24 апр 2024, 20:59

24 апр 2024, 20:59bc2d72c

using Custom.Linq.Extensions;

Console.WriteLine("MedianUsage");
MedianUsage();
Console.WriteLine();
Console.WriteLine("OverloadUsage");
OverloadUsage();
Console.WriteLine();
Console.WriteLine("GenericUsage");
GenericUsage();
Console.WriteLine();
Console.WriteLine("SequenceUsage");
SequenceUsage();

static void MedianUsage()
{
    // <MedianUsage>
    double[] numbers = [1.9, 2, 8, 4, 5.7, 6, 7.2, 0];
    var query = numbers.Median();

    Console.WriteLine($"double: Median = {query}");
    // This code produces the following output:
    //     double: Median = 4.85
    // </MedianUsage>
}
static void OverloadUsage()
{
    // <OverloadUsage>
    double[] numbers1 = [1.9, 2, 8, 4, 5.7, 6, 7.2, 0];
    var query1 = numbers1.Median();

    Console.WriteLine($"double: Median = {query1}");

    int[] numbers2 = [1, 2, 3, 4, 5];
    var query2 = numbers2.Median();

    Console.WriteLine($"int: Median = {query2}");
    // This code produces the following output:
    //     double: Median = 4.85
    //     int: Median = 3
    // </OverloadUsage>
}

static void GenericUsage()
{
    // <GenericUsage>
    int[] numbers3 = [1, 2, 3, 4, 5];

    /*
        You can use the num => num lambda expression as a parameter for the Median method
        so that the compiler will implicitly convert its value to double.
        If there is no implicit conversion, the compiler will display an error message.
    */
    var query3 = numbers3.Median(num => num);

    Console.WriteLine($"int: Median = {query3}");

    string[] numbers4 = ["one", "two", "three", "four", "five"];

    // With the generic overload, you can also use numeric properties of objects.
    var query4 = numbers4.Median(str => str.Length);

    Console.WriteLine($"string: Median = {query4}");
    // This code produces the following output:
    //     int: Median = 3
    //     string: Median = 4
    // </GenericUsage>
}

static void SequenceUsage()
{
    // <SequenceUsage>
    string[] strings = ["a", "b", "c", "d", "e"];

    var query5 = strings.AlternateElements();

    foreach (var element in query5)
    {
        Console.WriteLine(element);
    }
    // This code produces the following output:
    //     a
    //     c
    //     e
    // </SequenceUsage>
}