Become Child on Trigger Enter, but stop being Child when out of trigger

So I got this system were you can build spaceships with blocks (kinda like Starmade)

however the character cant walk around the ship he/she just glides off. So I have a chair with a trigger object
on the chair (a cube) so what I need is the moment the player walks into the trigger the player becomes child of the chair, (the chair is parent of the ship) but the moment the player walks out of the trigger it isnt a child anymore of the chair...

Anyone know how to do this because I did do triggers in the past but I have no idea how to do this

 

Code (csharp):

1.  
2. //put this in a script on the chair
3. public void OnTriggerEnter(Collider col)
4. {
5.     if(col.transform.CompareTag("MyDudesTag"))
6.     {
7.         col.transform.parent = transform;
8.         col.transform.localPosition = Vector3.zero;
9.     }
10. }
11.  
12. public void OnTriggerExit(Collider col)
13. {
14.     if(col.transform.CompareTag("MyDudesTag"))
15.     {
16.         col.transform.parent = null;
17.     }
18. }

 

don't set the local position to zero... less you'd rather the object teleport to <0,0,0> of the chair when you enter its collider.

 

So there are some errors, and i'm used to using Javascript, so it seems almost akward to ask you to take a look xD
It has something to do with Collider col

''A namespace can only contain types and namespace declarations'' on both line 2,13 and line 11,13