Have two variable types

Question

I am attempting to make a suvat calculator and require to have some form of way to have two different types of variable stored in one variable.

For those unaware of suvat. suvat equations are a collection of equations which allows for each of the five variables to be found from only three known variables.

This means that I need to be able to have a variable hold a float and a null value. Is there any way of doing this?

Possible duplicate of [How to assign Null value to Non-Nullable type variable in C#?](http://stackoverflow.com/questions/15491889/how-to-assign-null-value-to-non-nullable-type-variable-in-c) — Lance U. Matthews, Mar 25 '17 at 19:56

BoltBait · Accepted Answer · 2017-03-25T20:48:05.097

3

In order for a variable to hold both a float or null, you need to use nullable types. For example, you can use "float?" as the type:

float? myFloat = null;

If you need to hold a double or null, use the nullable double type:

double? myDouble = null;

etc.

edited Mar 25 '17 at 20:48

answered Mar 25 '17 at 19:52

BoltBait

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Also known as "[Nullable types](https://msdn.microsoft.com/en-us/library/1t3y8s4s.aspx)". – Uwe Keim Mar 25 '17 at 19:54
Unfortunately, this is pretty much what I need; however, I cannot seem to convert this type to a double. Each conversion I try doesn't allow me to use Math.sqrt(variable) – TheAndOnlyFin Mar 25 '17 at 20:35
@TheAndOnlyFin, after testing to be sure myFloat doesn't equal null, try: Math.Sqrt((double)myFloat); – BoltBait Mar 25 '17 at 20:44

score 0 · Answer 2 · answered Mar 25 '17 at 19:55

You can simply create a class that contains the types you need. For example, if you need a float and a string (you said null, but that is not a type, so I'm using string, which can be null):

class SomeClassName
{
    public float FloatValue {get; set;}
    public string StringValue {get; set;}
}

Now you can create a variable of type SomeClassName and assign it both a float and a string:

SomeClassName suvat = new SomeClassName();
suvat.FloatValue = 1.2;
suvat.StringValue = null;

Have two variable types

2 Answers2