Unity中InitializeOnLoad属性的妙用

using UnityEditor;
using UnityEngine;

[InitializeOnLoad]
class MyClass
{
    static string strFilePath;
    static DateTime lastModifyTime;

    static MyClass ()
    {
        EditorApplication.update += Update;
    }

    static void Update ()
    {
        DateTime time = File.GetLastWriteTime(strFilePath);

        if (lastModifyTime == time) return;

        lastModifyTime = time;

        // todo...
    }
}