Changing a UI image Based on Platform

Can anyone help me solve a problem with a script for multiplatform

I have a start menu that has a UI Image in Unity 5. The Image is supposed to change to change based on the platform in Use. the image is a press start sprite with the following button to match that platform

Here is an example

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 
 //Public class
 public class PlatformImage : MonoBehaviour 
 {
     //Request For Platform Specific Images
 
     //Desktops/Laptops
     public Sprite PC; //Windows or Linux
 
     //Consoles
     public Sprite PS4; //Playstation 4
     public Sprite XB1; //Xbox One
 
 
 
     // Use this for initialization
     void Start () 
     {
         //Windows
         #if UNITY_STANDALONE_WIN
         this.GetComponent<UnityEngine.UI.Image>();
 
         //PS4
           #elif UNITY_PS4
           this.GetComponent<UnityEngine>UI.Image>("PS4");
           #endif
 
     
 }

}

So what is happening, I am trying to figure out how to assign the proper sprite/Texture based on the platform the game is running on. Also the "#if UNITY_PS4" grays out my code under it as if it was commented out. What am I doing wrong here? I would like to solve this to save time by using one build for all systems and use certain code based on the system that is running the game.