关于func：C＃-如何传递对需要out变量的函数的引用？


C# - How can I pass a reference to a function that requires an out variable?

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public class Foo
{
    public void DoFoo()
    {
       int x;
       var coll = TheFunc("bar", out x);
    }

    public Func<string, int, ICollection<string>> TheFunc { get; set; }
}

错误："参数2不应与'out'关键字一起传递。"

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public class Foo
{
    public void DoFoo()
    {
       int x;
       var coll = TheFunc("bar", out x);
    }

    public Func<string, out int, ICollection<string>> TheFunc { get; set; }
}

错误："无效的方差修饰符。只能将接口和委托类型参数指定为变量。"

如何在此函数中获取out参数？

相关讨论

定义一个委托类型：

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public delegate ICollection<string> FooDelegate(string a, out int b);

public class Foo
{
    public void DoFoo()
    {
       int x;
       var coll = TheFunc("bar", out x);
    }

    public FooDelegate TheFunc { get; set; }
}

您需要创建自己的代表：

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delegate ICollection<string> MyFunc(string x, out int y);