Check out example codes for "unity ads tutorial 2020". It will help you in understanding the concepts better.

Code Example 1

using System.Collections;
using UnityEngine;
using UnityEngine.Advertisements;

// how to add a banner ad in unity games
public class BannerAdScript : MonoBehaviour {

    #if UNITY_IOS
    private string gameId = "1486551";
    #elif UNITY_ANDROID
    private string gameId = "1486550";
    #endif
    
    public string placementId = "bannerPlacement";
    public bool testMode = true;

    void Start () {
        // Initialize the SDK if you haven't already done so:
        Advertisement.Initialize (gameId, testMode);
        StartCoroutine (ShowBannerWhenReady ());
      
      // set the position
        Advertisement.Banner.SetPosition (BannerPosition.TOP_CENTER);

    }

    IEnumerator ShowBannerWhenReady () {
        while (!Advertisement.IsReady (placementId)) {
            yield return new WaitForSeconds (0.5f);
        }
        Advertisement.Banner.Show (placementId);
    }
}

Code Example 2

using UnityEngine;
using UnityEngine.Advertisements;

// how to make ads related to the player in unity games
public class InterstitialAdsScript : MonoBehaviour { 

    #if UNITY_IOS
    private string gameId = "1486551";
    #elif UNITY_ANDROID
    private string gameId = "1486550";
    #endif
    
    bool testMode = true;

    void Start () {
        // Initialize the Ads service:
        Advertisement.Initialize (gameId, testMode);
        // Show an ad:
        Advertisement.Show ();
    }
}

Code Example 3

using UnityEngine;
using UnityEngine.UI;
using UnityEngine.Advertisements;

// how to start a rewarded ad in unity games after pressign a button
[RequireComponent (typeof (Button))]
public class RewardedAdsButton : MonoBehaviour, IUnityAdsListener {

    #if UNITY_IOS
    private string gameId = "1486551";
    #elif UNITY_ANDROID
    private string gameId = "1486550";
    #endif

    Button myButton;
    public string myPlacementId = "rewardedVideo";

    void Start () {   
        myButton = GetComponent <Button> ();

        // Set interactivity to be dependent on the Placement’s status:
        myButton.interactable = Advertisement.IsReady (myPlacementId); 

        // Map the ShowRewardedVideo function to the button’s click listener:
        if (myButton) myButton.onClick.AddListener (ShowRewardedVideo);

        // Initialize the Ads listener and service:
        Advertisement.AddListener (this);
        Advertisement.Initialize (gameId, true);
    }

    // Implement a function for showing a rewarded video ad:
    void ShowRewardedVideo () {
        Advertisement.Show (myPlacementId);
    }

    // Implement IUnityAdsListener interface methods:
    public void OnUnityAdsReady (string placementId) {
        // If the ready Placement is rewarded, activate the button: 
        if (placementId == myPlacementId) {        
            myButton.interactable = true;
        }
    }

    public void OnUnityAdsDidFinish (string placementId, ShowResult showResult) {
        // Define conditional logic for each ad completion status:
        if (showResult == ShowResult.Finished) {
            // Reward the user for watching the ad to completion.
        } else if (showResult == ShowResult.Skipped) {
            // Do not reward the user for skipping the ad.
        } else if (showResult == ShowResult.Failed) {
            Debug.LogWarning (“The ad did not finish due to an error.”);
        }
    }

    public void OnUnityAdsDidError (string message) {
        // Log the error.
    }

    public void OnUnityAdsDidStart (string placementId) {
        // Optional actions to take when the end-users triggers an ad.
    } 
}

Code Example 4

using UnityEngine;
using UnityEngine.Advertisements;

// how to make rewarded scripts autometically in unity games
public class RewardedAdsScript : MonoBehaviour, IUnityAdsListener { 

    #if UNITY_IOS
    private string gameId = "1486551";
    #elif UNITY_ANDROID
    private string gameId = "1486550";
    #endif
    
   
    string myPlacementId = "rewardedVideo";
    bool testMode = true;

    // Initialize the Ads listener and service:
    void Start () {
        Advertisement.AddListener (this);
        Advertisement.Initialize (gameId, testMode);
    }

    // Implement IUnityAdsListener interface methods:
    public void OnUnityAdsDidFinish (string placementId, ShowResult showResult) {
        // Define conditional logic for each ad completion status:
        if (showResult == ShowResult.Finished) {
            // Reward the user for watching the ad to completion.
        } else if (showResult == ShowResult.Skipped) {
            // Do not reward the user for skipping the ad.
        } else if (showResult == ShowResult.Failed) {
            Debug.LogWarning ("The ad did not finish due to an error.");
        }
    }

    public void OnUnityAdsReady (string placementId) {
        // If the ready Placement is rewarded, show the ad:
        if (placementId == myPlacementId) {
            Advertisement.Show (myPlacementId);
        }
    }

    public void OnUnityAdsDidError (string message) {
        // Log the error.
    }

    public void OnUnityAdsDidStart (string placementId) {
        // Optional actions to take when the end-users triggers an ad.
    } 
}

Code Example 5

using UnityEngine;
using UnityEngine.Advertisements;

// how to initalize ads in unity games
public class InitializeAdsScript : MonoBehaviour { 

    #if UNITY_IOS
    private string gameId = "1486551";
    #elif UNITY_ANDROID
    private string gameId = "1486550";
    #endif
    
    bool testMode = true;

    void Start () {
        Advertisement.Initialize (gameId, testMode);
    }
}

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