How do I know whether variable is pass by value or by reference?

Questions & Answers
1

For example transform seems always pass by reference, so we usually use code like this:

myTr=transform;

When the object move, myTr also change.

But in other cases, Vector, for example, seems pass by value.

pos=transform.position;

The variable pos likely doesn’t change as object move. It’s a little confused sometimes.

2

Structs (Vector2, Vector3, Color, etc.) and primitive types (int, float, byte, etc.) are by value, everything else is by reference. The docs say whether something is a struct.

3

In C#, Value Types (struct,enum) are passed by value and Reference Types (class,interface,delegate) are passed by reference. You can pass a Value Type as reference using the ref keyword.

See MSDN Value Types and Reference Types.

4

Structs are passed as value and Classes are passed as reference.

If you want to pass a Struct as a reference, you can define the parameter in the function with ‘ref’ modifier

like for example:

void DoSomething(ref Vector3 vec)
{
    vec.y = 0;
}