c# - 有没有办法避免为每个 Func 参数计数使用 Func 参数重载方法

Question

我知道这个问题听起来有点奇怪。很抱歉，在尝试到达我想去的地方甚至解释它时遇到困难。为简单起见，我有一个方法 Func<T>争论。但我并不总是将无参数Action 传递给该方法，我需要不同 数量的参数，并且我正试图找到一种方法来避免重载 每当需要的参数数量增加时我的方法

这是我的通用类，我需要重载 GetInstance方法:

public class MethodResult<T>
{
    public T Result { get; set; }
    public bool IsResulted { get; set; }
    public Exception Error { get; set; }

    private MethodResult() { }

    public static MethodResult<T> GetInstance<T>(Func<T> method)
    {
        MethodResult<T> obj = new MethodResult<T>();

        try
        {
            obj.Result = method();
            obj.IsResulted = true;
            obj.Error = null;
        }
        catch (Exception ex)
        {
            obj.Result = default(T);
            obj.IsResulted = false;
            obj.Error = ex;
        }

        return obj;
    }

    public static MethodResult<T> GetInstance<T, T1>(Func<T1, T> method, T1 param1)
    {
        MethodResult<T> obj = new MethodResult<T>();

        try
        {
            obj.Result = method(param1);
            obj.IsResulted = true;
            obj.Error = null;
        }
        catch (Exception ex)
        {
            obj.Result = default(T);
            obj.IsResulted = false;
            obj.Error = ex;
        }

        return obj;
    }
}

下面是展示我想如何使用它的示例:

public static void Main(string[] args)
{            
        var x = MethodResult<int>.GetInstance(IntResult, 5);
        Console.WriteLine("Result: {0}, IsResulted: {1}, ErrorMessage: {2}", x.Result, x.IsResulted, (x.Error == null ? "null" : x.Error.Message));

        var y = MethodResult<string>.GetInstance(SayHello);
        Console.WriteLine("Result: {0}, IsResulted: {1}, ErrorMessage: {2}", y.Result, y.IsResulted, (y.Error == null ? "null" : y.Error.Message));

        Console.Read();
}

public static int IntResult(int x) { return x + 1; }
public static int IntResult(int x, int y) { return x + y; }
public static string SayHello() { return "Hello world!"; }

为了能够使用IntResult(int x, int y)我必须重载 GetInstance签名方法:

public static MethodResult<T> GetInstance<T, T1, T2>(Func<T1, T2, T> method, T1 param1, T2 param2)

很明显，这将变得非常耗时，因为它已经很烦人了。有没有办法避免那么多的重载？

Answer 1

您可以传递一个无参数匿名委托(delegate)，而不是传递要调用的函数和参数，从而调用您想要使用所需参数指向的方法.只需删除 GetInstance 的任何重载，只需保留:

public static MethodResult<T> GetInstance(Func<T> method)
{
    MethodResult<T> obj = new MethodResult<T>();

    try
    {
        obj.Result = method();
        obj.IsResulted = true;
        obj.Error = null;
    }
    catch (Exception ex)
    {
        obj.Result = default(T);
        obj.IsResulted = false;
        obj.Error = ex;
    }

    return obj;
}

然后调用如下:

int n = 1;
var x = MethodResult<string>.GetInstance(() => SayHello());
var y = MethodResult<string>.GetInstance(() => IntResult(2));
var z = MethodResult<int>.GetInstance(() => IntResult(n, 9));