The short type in C#-CodePudding

I am learning value types in C# and I noticed this:

when you hover over the value of a declared short, It says that It is a 32-bit int. I know that a short is a 16-bit int. Why isn't It recognizing It as an int, or maybe It does?

CodePudding user response：

you are hovering over the value (32000) which is an int/System.Int32 literal. There isn't a suffix for short to make a literal short. The compiler will do some gymnastics to ensure that it will fit. For instance, this should not compile.

int max = int.MaxValue;
short aShort = max;

CodePudding user response：

You should try to separate the declaration from the assignment of values

 -- declare       -- assign
|                |
short uwuhebfuyg = 3200;

Note that the declaration should be able to stand on its own, as the following is valid code

short uwuhebfuyg;

which could be assigned a value zero, one or more times later in code.

uwuhebfuyg = 100;
uwuhebfuyg = 16383;

Here the compiler interprets the digits as an integer and tries to fit it inside a short data type.

CodePudding user response：

Here's an explicit example of what's happening with the implicit conversion you're asking about.

Try this struct:

public struct NoMoreThanTwoCharacterString
{
    public string Value;
    public NoMoreThanTwoCharacterString(string source)
    {
        this.Value = source.Length <=2 ? source : source.Substring(0, 2);
    }

    public static implicit operator NoMoreThanTwoCharacterString(string source)
        => new NoMoreThanTwoCharacterString(source);
}

It defines a struct that holds a string that must not be longer than 2 characters. It defines an implicit operator than will allow any string to be assigned to a variable of type NoMoreThanTwoCharacterString.

You could use this type like this:

NoMoreThanTwoCharacterString x = "Hello";
Console.WriteLine(x.Value);

That writes out He to the console.

The type on the left of the = can be different to the type on the right. The implicit operator allows for the assignment to work, but in doing so it may need change the incoming value.