如何在Action中傳遞參數？

Question

private void Include(IList<string> includes, Action action)
{
    if (includes != null)
    {
        foreach (var include in includes)
            action(<add include here>);
    }
}

我想這樣稱呼它

this.Include(includes, _context.Cars.Include(<NEED TO PASS each include to here>));

這個想法是將每個包含傳遞給方法。

Answer 1

如果您知道要傳遞的參數，請為該類型執行Action<T> 。 例：

void LoopMethod (Action<int> code, int count) {
     for (int i = 0; i < count; i++) {
         code(i);
     }
}

如果要將參數傳遞給方法，請使方法通用：

void LoopMethod<T> (Action<T> code, int count, T paramater) {
     for (int i = 0; i < count; i++) {
         code(paramater);
     }
}

和來電者代碼：

Action<string> s = Console.WriteLine;
LoopMethod(s, 10, "Hello World");

---

更新。 您的代碼應如下所示：

private void Include(IList<string> includes, Action<string> action)
{
    if (includes != null)
    {
         foreach (var include in includes)
             action(include);
    }
}

public void test()
{
    Action<string> dg = (s) => {
        _context.Cars.Include(s);
    };
    this.Include(includes, dg);
}

Answer 2

你正在尋找Action<T> ，它接受一個參數。

Answer 3

臟技巧：您也可以使用lambda表達式傳遞您想要的任何代碼，包括帶參數的調用。

this.Include(includes, () =>
{
    _context.Cars.Include(<parameters>);
});