C#: Generate Separate Variable for Each Value in Array

Question

How can I store each element in a string array Joe, Ben, Carl into separate variables so that GuestA is Joe, GuestB is Ben, and GuestC is Carl without using a dictionary? (Notice that the variables are going in alphabetical order)

If you talk about doing this dynamically, why would you need that? — Yeldar Kurmangaliyev, Apr 17 '17 at 04:18
Possible duplicate of [Create dynamic variable name](http://stackoverflow.com/questions/20857773/create-dynamic-variable-name) — 41686d6564 stands w. Palestine, Apr 17 '17 at 04:30
Assuming that John Wu's answer isn't what you're looking for, and that you want the variables to be automatically created, what perceived benefit does that have over using a dictionary? How would you access such variable even if you could create them? — ProgrammingLlama, Apr 17 '17 at 04:58

score 2 · Answer 1 · answered Apr 17 '17 at 04:19

2

Not sure why you'd want to do this, but this code answers your question if taken literally.

string[] list = new string[] {"Joe","Ben","Carl"};
string GuestA = list[0];
string GuestB = list[1];
string GuestC = list[2];

Something tells me there are additional requirements that you are having trouble articulating.

answered Apr 17 '17 at 04:19

John Wu

50,556
8
44
80

I think what the OP meant is to do this dynamically. E.g. generate 26 variables with names `GuestA` to `GuestZ`. However, I'm not sure for what possible reason that would be a requirement. – 41686d6564 stands w. Palestine Apr 17 '17 at 04:25

score 0 · Accepted Answer · answered Apr 17 '17 at 05:06

Assuming you have GuestA, GuestB, and GuestC already declared, you'd use Reflection like this:

private string GuestA;
private string GuestB;
private string GuestC;

private void button1_Click(object sender, EventArgs e)
{
    string variableName;
    string[] values = {"Joe", "Ben", "Carl" };
    for(int i = 0; i < values.Length; i++)
    {
        variableName = "Guest" + Convert.ToChar(65 + i).ToString();
        System.Reflection.FieldInfo fi = this.GetType().GetField(variableName, System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic);
        if (fi != null)
        {
            fi.SetValue(this, values[i]);
        }
    }
}

Though I suspect this isn't quite what you've got since you used the word "Generate" in your title.

I think yours is close enough. In case anyone was wondering, I wanted to generate separate variables for each array element because I was trying to create a machine learning API that would generate a variable for each hidden layer that the user wanted to add. I hope this would clear up confusion. — ComputersAreCool, Apr 17 '17 at 17:37

score 0 · Answer 3 · answered Apr 17 '17 at 06:46

You can't use string like refrence type, but u can simulate reference behavoir by operators overloading, but in this case appears one big problem: inability for overloading assignment operator, in code below its bypasses through property-like style. But i think you can try doublQe assignment like Guest guestD = tempGuest = "Joe Ho"; (not sure about this).

public class ReferencedStringExample
{
    public void Wrong()
    {
        string GuestA = "Joe",
            GuestB = "Ben",
            GuestC = "Carl";

        var array = new string[]
        {
            GuestA,
            GuestB,
            GuestC
        };

        GuestA = "Joe Ho";

        Debug.Assert(GuestA == array[0]);            
    }

    public void Right()
    {
        Guest GuestA = "Joe",
            GuestB = "Ben",
            GuestC = "Carl";

        var array = new Guest[]
        {
            GuestA,
            GuestB,
            GuestC
        };

        GuestA.Val("Joe Ho");

        Debug.Assert(GuestA == array[0]);
        Debug.Assert(GuestA == "Joe Ho");

        GuestA = "Joe Ho";
        Debug.Assert(GuestA != array[0]);
        Debug.Assert(GuestA == "Joe Ho");
    }

    public class Guest
    {
        string value;

        public static implicit operator string(Guest g)
        {
            return g.value;
        }

        public static implicit operator Guest(string s)
        {
            return new Guest() { value = s };
        }
        public Guest Val(string s)
        {
            this.value = s;
            return this;
        }

        public override bool Equals(object obj)
        {
            Guest guest = obj as Guest;
            return guest.value == this.value;
        }
        public override int GetHashCode()
        {
            return (value ?? string.Empty).GetHashCode();
        }
    }
}

C#: Generate Separate Variable for Each Value in Array

3 Answers3