entry中添加了HMR相关文件，同时添加HMR插件以修复热重载不生效的问题

config/web/webpack.config.js

@@ -235,7 +235,14 @@ module.exports = function (webpackEnv) {
             (shouldUseSourceMap ? 'source-map' : isEnvStaging ? 'eval-cheap-module-source-map' : 'nosources-source-map'),
         // These are the "entry points" to our application.
         // This means they will be the "root" imports that are included in JS bundle.
-        entry: paths.appIndexJs,
+        entry: [
+            // 模块热替换的运行时代码
+            'webpack/hot/dev-server.js',
+            // 用于 web 套接字传输、热重载逻辑的 web server 客户端
+            'webpack-dev-server/client/index.js?hot=true&live-reload=true',
+            // oak项目入口
+            paths.appIndexJs,
+        ],
         output: {
             // The build folder.
             path: paths.appBuild,
@@ -802,6 +809,8 @@ module.exports = function (webpackEnv) {
                         : undefined
                 )
             ),
+            // 添加HMR插件支持
+            new webpack.HotModuleReplacementPlugin(),
             // Inlines the webpack runtime script. This script is too small to warrant
             // a network request.
             // https://github.com/facebook/create-react-app/issues/5358