Я использую ng serve --open, затем я получил сообщение
Could not find the implementation for builder @angular-devkit/build-angular:dev-server`enter code here`
Error: Could not find the implementation for builder @angular-devkit/build-angular:dev-server
at WorkspaceNodeModulesArchitectHost.resolveBuilder (C:\Users\Buddy4Study\desktop\angular_project\b4s-entry-v2\node_modules\@angular\cli\node_modules\@angular-devkit\architect\node\node-modules-architect-host.js:49:19)
at ServeCommand.initialize (C:\Users\Buddy4Study\desktop\angular_project\b4s-entry-v2\node_modules\@angular\cli\models\architect-command.js:72:63)
at <anonymous>
at process._tickCallback (internal/process/next_tick.js:188:7)
at Function.Module.runMain (module.js:678:11)
at startup (bootstrap_node.js:187:16)
at bootstrap_node.js:608:3