Why can a double var store an int type?

Question

Why a var of the kind double can store a var of the kind int?

Using C#

int x;
double y;

x = 5;
y = 2*x;

Console.WriteLine(x);
Console.WriteLine(y);
Console.ReadLine();

Answer 1

Let’s start calling things by the right name, then let’s call x and y variable, because var is a C# command and using that word can confuse what you’re talking about.

Then at the end I’d be saying

a variable of type double can store a variable of type int

Then I’ll correct the term once again, it’s meant to say:

a variable of type double can store a value of type int

Variable is one thing, value is another.

It turns out that a value of the type is not being stored int in y. The type of value stored there will always be of the type double because C# is a static typing language and the variable can only have a value of the type it was declared. Well, there is the question of null, but let’s leave it there so as not to confuse because in this case can not have this value.

So what happened? There was one cast implicit. Had a multiplication of two values of type int (2 and x) and the result of that which is also int is automatically converted to a value of the type double. Then effectively a value reconstruction operation in another format is performed (since int and double sane internally incompatible), even if it doesn’t seem to have it.

Automatic conversion is possible only in cases that have no data loss, and as whole value of int is a valid value in double the conversion is placed by the compiler.

Congratulations on your curiosity, just get used to using correct terms to communicate properly.