Platform-specific settings in Unity - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this platform check code?

Consider this Unity C# script snippet that checks the platform using preprocessor directives and prints a message. What will be printed if the game runs on an Android device?

Unity

using UnityEngine;

public class PlatformCheck : MonoBehaviour
{
    void Start()
    {
        #if UNITY_ANDROID
            Debug.Log("Running on Android");
        #elif UNITY_IOS
            Debug.Log("Running on iOS");
        #else
            Debug.Log("Running on another platform");
        #endif
    }
}

A Running on iOS

B Running on Android

C Running on another platform

D No output, code will not compile

💡 Hint

Look at the preprocessor directives and which one matches Android.

The #if UNITY_ANDROID directive compiles the code inside only when building for Android. So the Debug.Log prints "Running on Android" on Android devices.

❓ Predict Output

intermediate

What does this code print on Windows standalone build?

Given this Unity C# code snippet, what will be printed when running on a Windows standalone build?

Unity

using UnityEngine;

public class PlatformMessage : MonoBehaviour
{
    void Start()
    {
        if (Application.platform == RuntimePlatform.WindowsPlayer)
        {
            Debug.Log("Windows Standalone");
        }
        else
        {
            Debug.Log("Other Platform");
        }
    }
}

A Windows Standalone

B Other Platform

C No output

D Runtime error

💡 Hint

Check the Application.platform property and the RuntimePlatform enum.

Application.platform returns the current platform. On Windows standalone builds, it equals RuntimePlatform.WindowsPlayer, so it prints "Windows Standalone".

🔧 Debug

advanced

Why does this platform-specific code cause a compile error?

This Unity C# script uses platform-specific code but causes a compile error. Identify the cause.

Unity

using UnityEngine;

public class PlatformBug : MonoBehaviour
{
    void Start()
    {
        #if UNITY_IOS
            Debug.Log("iOS platform");
        #elif UNITY_ANDROID
            Debug.Log("Android platform");
        #else
            Debug.Log("Other platform");
        #endif

        #if UNITY_EDITOR
            Debug.Log("Editor mode");
        #endif

        #if UNITY_WIN
            Debug.Log("Standalone build");
        #endif
    }
}

A Using multiple #if directives in one method causes syntax errors.

B The code is correct and compiles without errors.

C UNITY_EDITOR cannot be used with other platform directives in the same method.

D UNITY_WIN is not a valid preprocessor directive, causing a compile error.

💡 Hint

Check Unity's official list of valid platform defines.

UNITY_WIN is not a valid preprocessor symbol. The correct symbols are UNITY_STANDALONE_WIN, UNITY_STANDALONE_OSX, or UNITY_STANDALONE_LINUX. Using UNITY_WIN causes a compile error.

📝 Syntax

advanced

Which option correctly uses platform-specific code to include a method only on iOS?

You want to include a method called ShowIosAlert() only when building for iOS. Which code snippet correctly uses preprocessor directives?

A

#if UNITY_IOS
public void ShowIosAlert() {
    Debug.Log("iOS Alert");
}
#endif

B

public void ShowIosAlert() {
#if UNITY_IOS
    Debug.Log("iOS Alert");
#endif
}

C

public void ShowIosAlert() {
#if UNITY_IOS
    Debug.Log("iOS Alert");
#else
    Debug.Log("Not iOS");
#endif
}

D

public void ShowIosAlert() {
#if UNITY_IPHONE
    Debug.Log("iOS Alert");
#endif
}

💡 Hint

Preprocessor directives can wrap entire methods to exclude them from compilation.

Option A wraps the entire method with #if UNITY_IOS ... #endif, so the method only exists in iOS builds. Option A compiles the method always but conditionally compiles the body, which can cause errors if called on other platforms. Option A includes the method always and has an else branch. Option A uses UNITY_IPHONE which is deprecated; UNITY_IOS is correct.

🚀 Application

expert

How to implement platform-specific file path handling in Unity?

You want to save a file in a platform-appropriate location in Unity. Which approach correctly handles platform-specific file paths?

A Use hardcoded absolute paths like "C:/MyGame/" for Windows and "/Documents/MyGame/" for iOS inside #if directives.

B Use Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments) for all platforms without Unity-specific paths.

C Use Application.persistentDataPath for all platforms and append platform-specific subfolders using #if directives.

D Use Application.dataPath for saving files on all platforms without any platform checks.

💡 Hint

Unity provides special paths that adapt to each platform's file system.

Application.persistentDataPath gives a safe, writable folder on all platforms. You can append platform-specific subfolders inside #if directives to organize files. Hardcoded absolute paths are unreliable and may cause permission issues. Application.dataPath is read-only on some platforms. Environment.GetFolderPath is not reliable across all Unity platforms.