KO CSharp Keyword new

Українська · Русский · English · Deutsch · Français · Italiano · Español · 繁體中文 · 日本語 · 한국어

C#: new

핸드북 C# · 실용 가이드

객체를 생성합니다. 수정자가 상속된 멤버를 명시적으로 숨기는 방법 일반 제약 조건에는 매개 변수가 없는 개방형 생성자가 필요하기 때문입니다.

간단한 예제 (Example.cs)

이 예제를 Example.cs로 따로 저장하고 이 페이지의 다른 예제와 독립적으로 실행하세요.

Example.cs:

// PROJECT-EXAMPLE
var child = new Child();
System.Console.WriteLine(child.Label);
System.Console.WriteLine(((Parent)child).Label);
class Parent { public string Label => "Parent"; }
class Child : Parent { public new string Label => "Child"; }

결과:

Child
Parent

통사론

new Type(...) / public new Member / where T : new()

예시 1: 기본 형태

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using System.IO;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices;

public static class Program
{
    public static async Task Main(string[] args)
    {
        Entity entity = new Player("Archer");
        Console.WriteLine(entity.Describe());
        Console.WriteLine(entity.Code);
    }
}
public interface ILabel { string Label { get; } }
public abstract class Entity : ILabel
{
    private readonly string name;
    protected Entity(string name) { this.name = name; }
    protected string Name => name;
    internal int Code { get; set; } = 7;
    public virtual string Label => Name;
    public abstract string Describe();
}
public sealed class Player : Entity
{
    public Player(string name) : base(name) { }
    public override string Label => "Player: " + base.Label;
    public override string Describe() => Label;
}

예 2: 또 다른 실제 형식

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using System.IO;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices;

public static class Program
{
    public static async Task Main(string[] args)
    {
        NamedCounter value = new();
        Console.WriteLine(value.Describe());
        Counter parent = value;
        Console.WriteLine(parent.Describe());
    }
}
public interface ICounter { int Count { get; } }
public class Counter : ICounter
{
    private int count;
    public Counter() : this(1) { }
    public Counter(int count) { this.count = count; }
    public int Count => count;
    protected internal virtual string Format() => count.ToString();
    public string Describe() => Format();
}
public sealed class NamedCounter : Counter
{
    public NamedCounter() : base(4) { }
    public new string Describe() => "Named: " + base.Describe();
    protected internal override string Format() => "Count=" + Count;
}

공식 출처: Microsoft 학습.