Unity 点击按钮，打开 Windows 文件选择框，并加载图片

代码如下：

using System;
using System.Collections;
using System.Runtime.InteropServices;
using UnityEngine;
using UnityEngine.Events;
using UnityEngine.Networking;
using UnityEngine.UI;/// <summary>
/// 文件日志类
/// </summary>
// [特性(布局种类.有序,字符集=字符集.自动)]
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public class OpenFileName
{public int structSize = 0;public IntPtr dlgOwner = IntPtr.Zero;public IntPtr instance = IntPtr.Zero;public String filter = null;public String customFilter = null;public int maxCustFilter = 0;public int filterIndex = 0;public String file = null;public int maxFile = 0;public String fileTitle = null;public int maxFileTitle = 0;public String initialDir = null;public String title = null;public int flags = 0;public short fileOffset = 0;public short fileExtension = 0;public String defExt = null;public IntPtr custData = IntPtr.Zero;public IntPtr hook = IntPtr.Zero;public String templateName = null;public IntPtr reservedPtr = IntPtr.Zero;public int reservedInt = 0;public int flagsEx = 0;public OpenFileName(){this.structSize = Marshal.SizeOf(this);this.filter = "Texure Files(*图片文件)\0*.png;*.jpg;*.bmp;*.jpeg\0";this.file = new string(new char[256]);this.maxFile = this.file.Length;this.fileTitle = new string(new char[64]);this.maxFileTitle = this.fileTitle.Length;this.initialDir = "C:\\"; //默认路径this.title = "打开项目";this.defExt = "JPG";this.flags = 0x00080000 | 0x00001000 | 0x00000800 | 0x00000200 | 0x00000008;}
}public class OpenFileHandle : MonoBehaviour
{public Button BtnOpenFile;public Image showImg;//打开文件[DllImport("Comdlg32.dll", SetLastError = true, ThrowOnUnmappableChar = true, CharSet = CharSet.Auto)]public static extern bool GetOpenFileName([In, Out] OpenFileName ofd);void Start(){BtnOpenFile.onClick.AddListener(BtnOpenFileEvent);}void BtnOpenFileEvent(){OpenFileName path = new OpenFileName();if (GetOpenFileName(path)){string filepath = path.file;StartCoroutine(ReadTexture(filepath, LoadImg));}}/// <summary>/// 读取图片/// </summary>/// <param name="path"></param>/// <param name="action"></param>/// <returns></returns>IEnumerator ReadTexture(string path, UnityAction<Texture> action){Debug.Log(path);UnityWebRequest request = UnityWebRequestTexture.GetTexture(path);yield return request.SendWebRequest();if (request.isNetworkError || request.isHttpError){Debug.Log(request.error);}else{byte[] imgdata = request.downloadHandler.data;action(DownloadHandlerTexture.GetContent(request));}}/// <summary>/// 加载图片/// </summary>/// <param name="texture"></param>void LoadImg(Texture texture){Sprite ImgSprite = Sprite.Create((Texture2D)texture, new Rect(0, 0, texture.width, texture.height), new Vector2(0.5f, 0.5f));showImg.sprite = ImgSprite;}
}

实现效果如下：