Implementing banner ads in Unity#

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.Advertisements;
 
public class BannerAdExample : MonoBehaviour
{
    // For the purpose of this example, these buttons are for functionality testing:
    [SerializeField] Button _loadBannerButton;
    [SerializeField] Button _showBannerButton;
    [SerializeField] Button _hideBannerButton;
 
    [SerializeField] BannerPosition _bannerPosition = BannerPosition.BOTTOM_CENTER;
 
    [SerializeField] string _androidAdUnitId = "Banner_Android";
    [SerializeField] string _iOSAdUnitId = "Banner_iOS";
    string _adUnitId = null; // This will remain null for unsupported platforms.
 
    void Start()
    {
        // Get the Ad Unit ID for the current platform:
#if UNITY_IOS
        _adUnitId = _iOSAdUnitId;
#elif UNITY_ANDROID
        _adUnitId = _androidAdUnitId;
#endif

        // Disable the button until an ad is ready to show:
        _showBannerButton.interactable = false;
        _hideBannerButton.interactable = false;
 
        // Set the banner position:
        Advertisement.Banner.SetPosition(_bannerPosition);
 
        // Configure the Load Banner button to call the LoadBanner() method when clicked:
        _loadBannerButton.onClick.AddListener(LoadBanner);
        _loadBannerButton.interactable = true;
    }
 
    // Implement a method to call when the Load Banner button is clicked:
    public void LoadBanner()
    {
        // Set up options to notify the SDK of load events:
        BannerLoadOptions options = new BannerLoadOptions
        {
            loadCallback = OnBannerLoaded,
            errorCallback = OnBannerError
        };
 
        // Load the Ad Unit with banner content:
        Advertisement.Banner.Load(_adUnitId, options);
    }
 
    // Implement code to execute when the loadCallback event triggers:
    void OnBannerLoaded()
    {
        Debug.Log("Banner loaded");
 
        // Configure the Show Banner button to call the ShowBannerAd() method when clicked:
        _showBannerButton.onClick.AddListener(ShowBannerAd);
        // Configure the Hide Banner button to call the HideBannerAd() method when clicked:
        _hideBannerButton.onClick.AddListener(HideBannerAd);
 
        // Enable both buttons:
        _showBannerButton.interactable = true;
        _hideBannerButton.interactable = true;     
    }
 
    // Implement code to execute when the load errorCallback event triggers:
    void OnBannerError(string message)
    {
        Debug.Log($"Banner Error: {message}");
        // Optionally execute additional code, such as attempting to load another ad.
    }
 
    // Implement a method to call when the Show Banner button is clicked:
    void ShowBannerAd()
    {
        // Set up options to notify the SDK of show events:
        BannerOptions options = new BannerOptions
        {
            clickCallback = OnBannerClicked,
            hideCallback = OnBannerHidden,
            showCallback = OnBannerShown
        };
 
        // Show the loaded Banner Ad Unit:
        Advertisement.Banner.Show(_adUnitId, options);
    }
 
    // Implement a method to call when the Hide Banner button is clicked:
    void HideBannerAd()
    {
        // Hide the banner:
        Advertisement.Banner.Hide();
    }
 
    void OnBannerClicked() { }
    void OnBannerShown() { }
    void OnBannerHidden() { }
 
    void OnDestroy()
    {
        // Clean up the listeners:
        _loadBannerButton.onClick.RemoveAllListeners();
        _showBannerButton.onClick.RemoveAllListeners();
        _hideBannerButton.onClick.RemoveAllListeners();
    }
}

Advertisement.Banner.SetPosition (BannerPosition.TOP_CENTER);