How to make the ui always align the camera?

I want to the following UI.
The ui is always align to camera, how to do it?

i try sth like create ui in world space and rotation = camera rotation.
It not look same.
Plz help or tell me the key words to let me search.
I really dk the key words...
i will be glad if someone try to help me

 

Easiest way is to set it to screen space.

For world space canvases simply call transform.LookAt(Camera.main.transform) in Update or LateUpdate.

Edit: Or simply do transfom.rotation = Camera.main.transform.rotation. Probably more performant.

 

would the edited in line make the ui face away from the camera? I think you'd need the inverse. apparently not

Code (csharp):

1.  
2. public class RotateTowardsCamera : MonoBehaviour
3. {
4.     public Camera target;
5.  
6.     void Start ()
7.     {
8.        if(!target)
9.         {
10.             target = Camera.main;
11.         }
12.     }
13.  
14.     void Update ()
15.     {
16.         Quaternion cameraRotation = target.transform.rotation;
17. // optionally ignore all but the y rotation, if you want it to be "square on" to the camera comment out the next line
18.         cameraRotation = Quaternion.Euler(0, cameraRotation.eulerAngles.y, 0);
19.         transform.rotation = cameraRotation;
20.     }
21. }
22.