C＃：如何将参数键/值传递给函数？

Question

I have a function that takes in a bool, shown below:

public void LoadEndPoints(bool mock)
{

}

I can call this via LoadEndpoints(true) or LoadEndpoints(false), but this can be a bit hard to understand, as you need to know what true/false represents. Is there a way to pass the parameter name and value to a function such as LoadEndPoints(mock = true)?

Answer 1

Yes!

You can specify the parameter names like this:

myObject.LoadEndPoints(mock: true);

Further Reading

• Named and Optional Arguments (C# Programming Guide)

Another way to improve readability of your code would be to use an enum, like this:

public enum LoadOption
{
    Normal,
    Mock
}

public void LoadEndPoints(LoadOption option)
{
    ...
}

Then the call would look a bit like this:

myObject.LoadEndPoints(LoadOption.Mock);

Answer 2

You could use 'Named arguments', a C# 4.0 feature; and thus call: myObject.LoadEndPoints(mock : true);

If readability is indeed your prime concern, you could even expose two explicit methods, and internally reuse the logic - something similar to:

    public void LoadEndPointsWithoutMock()
    {
        LoadEndPoints(false);
    }
    public void LoadEndPointsByMocking()
    {
        LoadEndPoints(true);
    }
    private void LoadEndPoints(bool mock)
    {

    }

Also, I wouldn't say that LoadEndPointsWithoutMock , etc. are great method names. Ideally, the names should have something to do with the domain.

Answer 3

您可以使用KeyValuePair：

   KeyValuePair kvp = new KeyValuePair(BoolType, BoolValue)

Answer 4

Yes, you can do it with the following syntax in c#:

myObject.LoadEndPoints(mock : true);

And in VB:

myObject.LoadEndPoints(mock := true)

Answer 5

Use named parameters. Have a look at this Named and Optional Arguments