EditorTemplate.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
#if UNITY_EDITOR
using UnityEditor;
#endif

[ExecuteInEditMode]
public class EditorTemplate : MonoBehaviour {

	// Use this for initialization
	void Start () {
		
	}
	
	// Update is called once per frame
	void Update () {
		
	}

	public void Act()
	{
		Debug.Log("Act");
	}
}


#if UNITY_EDITOR
[CustomEditor(typeof(EditorTemplate))]
class EditorTemplateEditor : Editor {
	override public void OnInspectorGUI () {
		EditorTemplate _target = (EditorTemplate)target;

		if (GUILayout.Button ("Act")) {
			_target.Act ();
		}

		if(_target != null){
			DrawDefaultInspector();
			EditorGUIUtility.labelWidth = 25;
			EditorGUIUtility.fieldWidth = 50;
		}
	}
}
#endif