Problems with OnTriggerEnter

Ok so anyway I am trying to create a script where when the player enters an area a gui pops up and he takes damage like a radiation zone to stop him from going out of the map. Heres my script don’t really know what’s wrong with it. and by the way the character is a cube and the area i am entering is also a cube just without the mesh render with is trigger selected under box collider!

var showgui : boolean = false;
public var myskin : GUISkin;
function OnCollisionEnter (col : Collision) {
if(col.gameObject.Tag == "Player"){
PlayerStats.curHp -= 100;
showgui = true;
function OnGUI ()
{ = myskin;
	if (showgui)

Make sure your player cube has a RigidBody on it. Make sure the above script is on the cube being entered, not on the cube that is moving. Put the following after ‘showgui = true;’:

Debug.Log (‘radiation zone entered’);

and see if it ever shows in the console. Also read the manual about using the Mono debugger. It’s really important to learn to use that.