What is wrong with this the return of this bool?

Question

The input bool is not being set to boolToSet:

bool SwitchToOpposite(bool boolToSet)
{
    if (boolToSet)
        boolToSet = false;
    else
        boolToSet = true;
    return boolToSet;
}

What do I need to do in order for it to return the boolToSet? Edit: here's the way I'm calling the method

public void OnFollowButton(InputAction.CallbackContext context)
{
    if (context.performed)
    {
        SwitchToOpposite(pressingFollowButton);
    }
}

Answer 1

If you want to set boolToSet field or property within a class, use this. prefix to address this field / property, e.g.

// Field within then class
private bool boolToSet;   

// A method to change boolToSet field
bool SwitchToOpposite(bool boolToSet)
{
    // We chech the argument passed  
    if (boolToSet)
        // but change the field which belongs to object
        this.boolToSet = false;
    else
        this.boolToSet = true;

    // we return changed value, not the argument of the method  
    return this.boolToSet;
}

Note, that you can simplify the code:

// A method to change boolToSet field
bool SwitchToOpposite(bool boolToSet)
{
    // Set (NOT boolToSet) to boolToSet field and return it
    return this.boolToSet = !boolToSet;
}

If you want to change the static field of property ("global"), you should use class name instead of this., e.g.

public class MyClass {
    ...
    // Static ("global") field within then class 
    public static bool boolToSet;   

    ...
}

...

// A method to change boolToSet field
bool SwitchToOpposite(bool boolToSet)
{
    // We check the argument passed  
    if (boolToSet)
        // but change the field which belongs to object
        MyClass.boolToSet = false;
    else
        MyClass.boolToSet = true;

    // we return changed value, not the argument of the method  
    return MyClass.boolToSet;
}