[Unity编辑器]通过拖拽获取文件路径

 using UnityEngine;
 using System.Collections;
 using UnityEditor;

 public class TestDrag : EditorWindow {

     string path;
     Rect rect;

     [MenuItem("Window/TestDrag")]
     static void Init()
     {
         EditorWindow.GetWindow(typeof(TestDrag));
     }

     void OnGUI()
     {
         EditorGUILayout.LabelField("路径");
         //获得一个长300的框
         rect = EditorGUILayout.GetControlRect(GUILayout.Width(300));
         //将上面的框作为文本输入框
         path = EditorGUI.TextField(rect, path);

         //如果鼠标正在拖拽中或拖拽结束时，并且鼠标所在位置在文本输入框内
         if ((Event.current.type == EventType.DragUpdated
           || Event.current.type == EventType.DragExited)
           && rect.Contains(Event.current.mousePosition))
         {
             //改变鼠标的外表
             DragAndDrop.visualMode = DragAndDropVisualMode.Generic;
             if (DragAndDrop.paths != null && DragAndDrop.paths.Length > 0)
             {
                 path = DragAndDrop.paths[0];
             }
         }
     }
 }