// Type definitions for serve-static 1.13
// Project: https://github.com/expressjs/serve-static
// Definitions by: Uros Smolnik <https://github.com/urossmolnik>
//         Linus Unnebäck <https://github.com/LinusU>
// Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
// TypeScript Version: 2.2

/* =================== USAGE ===================

  import * as serveStatic from "serve-static";
  app.use(serveStatic("public/ftp", {"index": ["default.html", "default.htm"]}))

 =============================================== */

/// <reference types="express-serve-static-core" />

import * as express from "express-serve-static-core";
import * as m from "mime";

/**
 * Create a new middleware function to serve files from within a given root directory.
 * The file to serve will be determined by combining req.url with the provided root directory.
 * When a file is not found, instead of sending a 404 response, this module will instead call next() to move on to the next middleware, allowing for stacking and fall-backs.
 */
declare function serveStatic(root: string, options"dotfiles" are treated when encountered. A dotfile is a file or directory that begins with a dot (".").
     * Note this check is done on the path itself without checking if the path actually exists on the disk.
     * If root is specified, only the dotfiles above the root are checked (i.e. the root itself can be within a dotfile when when set to "deny").
     * The default value is 'ignore'.
     * 'allow' No special treatment for dotfiles
     * 'deny' Send a 403 for any request for a dotfile
     * 'ignore' Pretend like the dotfile does not exist and call next()
     */
    dotfiles"index.html" files in response to a request on a directory.
     * To disable this set false or to supply a new index pass a string or an array in preferred order.
     */
    index"/" when the pathname is a dir. Defaults to true.
     */
    redirect"color: #ff0000">3、使用方式：

说明：源码中的注释说的很清楚用法，由于现阶段技术有限，博主将项目目录作为文件地址来简单的使用。
代码使用：只需要一句代码：
在 main.ts文件中：


 //...
  import * as serveStatic from 'serve-static';
  async function bootstrap() {
  const app = await NestFactory.create(AppModule);
  //....
  // 使用serve-static
  // '/public' 是路由名称，即你访问的路径为：host/public
  // serveStatic 为 serve-static 导入的中间件，其中'../public' 为本项目相对于src目录的绝对地址
  app.use('/public', serveStatic(path.join(__dirname, '../public'), {
   maxAge: '1d',
   extensions: ['jpg', 'jpeg', 'png', 'gif'],
  }));
  //....
  await app.startAllMicroservicesAsync();
  await app.listen(9871);
}
bootstrap();



在项目根目录下创建public目录：

目录创建.png
4、测试效果：
首先使用nestjs自带的upload api来上传文件，这里不做过多说明，最终通过postman完成测试文件上传：

测试上传.png
再使用浏览器浏览：

浏览图片.gif
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。