Return 2 strings with function in C# [duplicate]

问题:

This question already has an answer here:

Return multiple values from a class to method (1 answer)

Closed 6 years ago.

I have a function where I want to return 2 values? Is this possible?

This is my code but it doesn't seem to like that I want to return 2 values

public string PlayerCards(string player1C1, string player1C2)
        {

            generatedCard = randomCard.Next(1, 52);
            player1C1 = generatedCard.ToString();
            player1C1 = player1C1 + ".png";
            return player1C1, player1C2;
        }

I did some googling but I didn't find what I need.

回答1:

Some options:

• Use an out parameter:

  public string PlayerCards(out string x)
  

  Return one value, and set the out parameter (x in this case) to another value; the calling code will need to specify an argument with out as well, and after the call has completed, the caller will be able to see the value set in the method.

  (It's not clear why you're accepting parameters at all; you don't seem to really use them.)

• Return a ValueTuple<string, string>, ideally using C# 7 tuples to provide element names

• Return a Tuple<string, string>
• Create a new type to store the two values together, assuming it's a meaningful combination. This is definitely a good choice if the values are related in a way which you'll use elsewhere. For example, instead of having a method returning one string for the suit of a card and one for the value, you'd create a PlayingCard type.
• Refactor your code into two method calls, each of which return a single value

It's not at all clear what your code is trying to do - the name of the method isn't clear and you don't use the parameters. When you've clarified what the method is trying to achieve - to yourself as much as to us - the answer may well become more obvious.

I'd also encourage you to use local variables where appropriate - I suspect generatedCard should be a local variable instead of the (presumably) instance variable it currently is.

回答2:

you can return tuple: Tuple<string, string>

Tuple<string, string> t = new Tuple<string, string>(player1C1,player1C2);

return t;

回答3:

One of the several possible options:

Create a struct like this:

struct Players
{
  public string Player1;
  public string Player2;
}

Then use it in your function like this:

public Players PlayerCards()
    {   
        Players p1;
        generatedCard = randomCard.Next(1, 52);
        p1.Player1 = generatedCard.ToString();
        p1.Player2 =  p1.Player1 + ".png";            
        return p1;
    }

回答4:

I think that you can use string array...

Second way is to use a struct containing two string values or a class with two string member,,

Look at here:

    /// <summary>
    /// Using struct
    /// </summary>
    struct twoStringValue
    {
        public string s1, s2;
    }

    public twoStringValue PlayerCards(string player1C1, string player1C2)
    {
        twoStringValue tsv;
        generatedCard = randomCard.Next(1, 52);
        tsv.s1 = player1C1 = generatedCard.ToString();
        tsv.s1 = player1C1 = player1C1 + ".png";
        return tsv;
    }


    /// <summary>
    /// Using a class
    /// </summary>
    class TwoStringValue
    {
        public string str1;
        public string str2;
    }

    public TwoStringValue PlayerCards(string player1C1, string player1C2)
    {
        TwoStringValue tsv;
        generatedCard = randomCard.Next(1, 52);
        tsv.str1 = player1C1 = generatedCard.ToString();
        tsv.str1 = player1C1 = player1C1 + ".png";
        return tsv;
    }

Good Luck.