Search directories for buddy

using System.Collections;
using System.IO;
using UnityEditor;
using UnityEngine;

public class Synchronize : EditorWindow
{
    [MenuItem("Ultimate MMORPG Kit/Synchronize NPC")]
    public static void ShowWindow()
    {
        EditorWindow.GetWindow(typeof(Synchronize));
        isPositive = false;
        path = string.Empty;
    }

    string[] appPath = Application.dataPath.Split('/');
    static string path = string.Empty;
    string[] client2;
    static bool isPositive;
    string fileS = string.Empty;
    string pathS = Application.dataPath + "/UMK_Files/NPCfile.umk";
    bool isOn;

    void OnGUI()
    {
        if(!isPositive)
        {
            for(int i = 0; i < appPath.Length - 3; i++)
            {
                path += appPath[i]  + "/";
            }

            isPositive = true;
        }

        GUILayout.Space(10);
        if(GUILayout.Button("Synchronize NPCs", GUILayout.Width(350), GUILayout.Height(40)))
        {
            client2 = Directory.GetFiles(path, "NPCfileC.umk", SearchOption.AllDirectories);
            isOn = true;
            if(client2.Length > 0)
            {
                isOn = false;
                fileS = client2[0];
                string str1;

                using (System.IO.StreamReader reader = System.IO.File.OpenText(pathS))
                {
                    str1 = reader.ReadToEnd();
                }

                using (System.IO.StreamWriter file = new System.IO.StreamWriter(fileS))
                {
                    file.Write(str1);
                }
            }
        }

        if(client2 != null)
        {
            if(client2.Length == 0 && isOn)
            {
                GUILayout.Label("Set the NPC Editor in the Client's Project firstly!", EditorStyles.boldLabel);
            }
        }
    }
}