Cant change sprite via code in NGUI free

[piearesquared0]

 Ive had alot of trouble with this and im not sure if it because of my lack of experience with NGUI or lack of skill in unity, i try everything i can think of to change the sprite via code (tried both cs and js) and i get an error everytime

this

1. void Update ()
2.         {
3.                 UISlicedSprite spr;
4.                 spr=this.GetComponent(UISlicedSprite);
5.                 spr.spriteName=items.items[id].name;
6.         }
7.  

this

1. void Update ()
2.         {
3.                 UISlicedSprite spr;
4.                 spr=GetComponent(UISlicedSprite);
5.                 spr.spriteName=items.items[id].name;
6.         }
7.  

this

1. void Update ()
2.         {
3.                 UISlicedSprite spr;
4.                 spr=this.gameObject.GetComponent(UISlicedSprite);
5.                 spr.spriteName=items.items[id].name;
6.         }
7.  

and every time i get loads of errors dealing with type conversions

_{Assets/scripts/engine/system/invItemBox.cs(17,39): error CS0119: Expression denotes a `type', where a `variable', `value' or `method group' was expected
Assets/scripts/engine/system/invItemBox.cs(17,26): error CS1502: The best overloaded method match for `UnityEngine.Component.GetComponent(System.Type)' has some invalid arguments
Assets/scripts/engine/system/invItemBox.cs(17,26): error CS1503: Argument `#1' cannot convert `object' expression to type `System.Type'}

ive even tried replacing the () with <> and that just adds more errors, please help!

[Nicki]

Getcomponent is written like this

1. spr = GetComponent<UISlicedSprite>();