How do you attach a script to a game object in Unity 2D version 4.5.1?

I am reading a book titled “LEARNING 2D GAME DEVELOPMENT WITH UNITY” by Matthew Johnson/James A. Henley

It teaches on version 4.5.1 unity 2D. Everytime I click and drag a script written in the book to my player game object I get an error message

“Can’t add component right script because it doesn’t exist. Check to see if the file name and class name match”

I’m stuck in chapter 5 for this reason. What do I do from this point. What is Class name and why does it say my file doesn’t exist when I just created it in Mono.

Can anyone who understands what I’m writing here or maybe you have read this entire book before help me out.



When you create c# scripts in Unity, the filename needs to match the class name. For example:

MyFirstClass.cs (This is the filename)

using UnityEngine;
using System.Collections;

public class MyFirstClass : MonoBehaviour {

Notice right after “public class” it says MyFirstClass? That’s the class name.

The class and the file need to be the same, well the file needs the .cs extension. But hopefully you get the idea now. Case sensitive btw