Unity/Editor/メニュー追加

Assets/Scripts/Editor/CustomMenu.cs

using UnityEngine;
using UnityEditor;
public class CustomMenu
{
    [MenuItem("CustomMenu/CustomItem1 %i")]
    private static void CustomItem1()
    {
        Debug.Log("item1");
    }
    [MenuItem("CustomMenu/CustomItem2 %h")]
    private static void CustomItem2()
    {
        Debug.Log("item2");
    }
}

namespace name 'MenuItem'エラーが出る場合

以下エラーが出るとき

namespace name 'MenuItem' could not be found (are you missing a using directive or an assembly reference?)

using UnityEditor;を追加