C# Loops in Unity – Master for and while for Game Logic

Imagine spawning 5 enemies, checking every platform for coins, or counting down a timer.
Typing the same code 10 times? Nah.
That’s what loops are for.

In this lesson, we’ll cover the two most common types of loops in C#:
for loops and while loops.

🔄 What is a Loop?

A loop lets you repeat a block of code multiple times.

It’s like telling Unity: “Hey, do this thing again — but only until I say stop.”

🎯 `for` Loop – Counted Repetition

for (int i = 0; i < 5; i++)
{
    Debug.Log("Spawning enemy #" + i);
}

What’s happening here?

int i = 0 → Start at 0
i < 5 → Keep going as long as i is less than 5
i++ → Add 1 each time

This prints 5 messages — once per enemy. Great for counted repetition.

🔁 `while` Loop – Repeat Until a Condition Changes

int lives = 3;

while (lives > 0)
{
    Debug.Log("Still alive!");
    lives--;
}

This runs as long as lives is more than 0.
Each time through, it prints the message and decreases lives.

Be careful! A while loop won’t stop unless the condition eventually becomes false. That’s how infinite loops happen 🌀

🧪 Unity Example – Spawning Objects with a Loop

Here’s a simple for loop in Unity that spawns 5 cubes in a row:

using UnityEngine;

public class Spawner : MonoBehaviour
{
    public GameObject cubePrefab;

    void Start()
    {
        for (int i = 0; i < 5; i++)
        {
            Vector3 spawnPosition = new Vector3(i * 2, 0, 0);
            Instantiate(cubePrefab, spawnPosition, Quaternion.identity);
        }
    }
}

Attach this script to an empty GameObject
Assign a prefab in the Inspector
Hit play and voilà – five glorious cubes

🧠 When to Use What?

Use `for` when…	Use `while` when…
You know how many times to repeat	You don’t know how long it’ll last
You’re counting something	You’re waiting for a condition
Performance loops	Wait timers, player input

💥 Common Mistake: Infinite Loops

while (true)
{
    Debug.Log("Wheeeeee!");
}

Unless you’re a fan of frozen editors, don’t do this without a break condition!
Unity will get stuck, and you’ll become best friends with the Task Manager.

🧠 Recap

for loops = best for doing things a set number of times
while loops = best for doing something until a condition changes
Combine loops with other logic for powerful effects
Loops are perfect for spawning, timers, and repeating animations

🧪 Mini Challenge: Make a Star Row

Create a prefab (e.g. a star sprite)
Create a script StarSpawner.cs
In Start(), use a for loop to spawn 10 stars in a line
Use the loop variable to space them evenly (like i * 1.5f)

Bonus: Add a public int starCount to control how many are spawned.

🚀 What’s Next?

You’ve now got variables, methods, logic, and loops! It’s time to combine everything into a simple class to represent real objects in your game.

👤 Go to Lesson 11 → Classes and Objects in Unity C#

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