angular - ERROR in Error 遇到静态解析符号值

Question

我刚刚在 angular-cli 下迁移了我的项目，当我启动它时出现了这个错误:

ERROR in Error encountered resolving symbol values statically. Function calls are not supported. Consider replacing the function or lambda with a reference to an exported function (position 63:45 in the original .ts file), resolving symbol AppModule in C:/Data/Private/Innovation/EV/ev-dashboard/src/app/app.module.ts

对应app.module.ts中的APP_INITIALIZER:

...
providers: [ // expose our Services and Providers into Angular's dependency injection
    APP_PROVIDERS,
    ConfigService,
    { provide: APP_INITIALIZER, useFactory: (config: ConfigService) => () => config.load(), deps: [ConfigService], multi: true }
...

有趣的是，当我评论这一行时，它开始很好，然后取消评论，这一次触发编译没有错误!!!

你有什么想法吗？

谢谢，哔叽。

Answer 1

你需要像这样提取函数:

export function configFactory(config: ConfigService) {
  return () => config.load()
}

...
providers: [{ 
  provide: APP_INITIALIZER, 
  useFactory: configFactory, 
  deps: [ConfigService], 
  multi: true 
}

另见

• https://github.com/angular/angular/issues/11262

• Angular4 APP_INITIALIZER won't delay initialization