unity 把文件拖入自定义EditorWindow

using UnityEditor;
using UnityEngine;

public class StringEncrypter : EditorWindow
{
    
    
    [MenuItem("MyPlugins/open window", false)]
    public static void open()
    {
    
    
        StringEncrypter _stringEncrypter = GetWindow<StringEncrypter>(true, "window");
    }

    private string[] filePaths = null;

    private string tip;


    private void OnGUI()
    {
    
    
        if (mouseOverWindow == this)
        {
    
    
            //鼠标位于当前窗口
            if (Event.current.type == EventType.DragUpdated)
            {
    
    
                //拖入窗口未松开鼠标
                DragAndDrop.visualMode = DragAndDropVisualMode.Generic; //改变鼠标外观
            }
            else if (Event.current.type == EventType.DragExited)
            {
    
    
                //拖入窗口并松开鼠标
                Focus(); //获取焦点，使unity置顶(在其他窗口的前面)
                //Rect rect=EditorGUILayout.GetControlRect();
                //rect.Contains(Event.current.mousePosition);//可以使用鼠标位置判断进入指定区域
                if (DragAndDrop.paths != null)
                {
    
    
                    filePaths = DragAndDrop.paths;
                    Event.current.Use();
                }
            }
        }

        //File.GetAttributes(path).CompareTo(FileAttributes.Directory) != 0

        if (!string.IsNullOrEmpty(tip))
        {
    
    
            GUIStyle style2 = new GUIStyle();
            style2.fontSize = 20;
            style2.alignment = TextAnchor.MiddleCenter;
            GUILayout.Label(tip, style2);
        }
    }
}