正确理解 angular14 中的注入 必须从注入上下文中调用注入()

我正在努力学习angular 14中的变化，特别是inject()特性，在这里我可以将模块注入函数，而不需要为此创建特殊服务..但我想我做错了什么.

我试图创建一些静态函数来使用包ngx-toastr发送零食消息，但这个包与我的问题无关.我如何正确地实现显示零食消息的功能，同时向它们注入它们需要操作的模块.

这是我的messages.ts文件:

import {inject} from '@angular/core';
import {ToastrService} from 'ngx-toastr';


export const snackMsgSuccess = (msg: string, title?: string) => {
  const toaster = inject(ToastrService);
  toaster.success(msg, title, {
    easeTime: 1000
  });
};


export const snackMsgInfo = (msg: string, title?: string) => {
  const toaster = inject(ToastrService);
  toaster.info(msg, title, {
    easeTime: 1000
  });
};

export const snackMsgWarn = (msg: string, title?: string) => {
  const toaster = inject(ToastrService);
  toaster.warning(msg, title, {
    easeTime: 1000
  });
};


export const snackMsgError = (msg: string, title?: string) => {
  const toaster = inject(ToastrService);
  toaster.error(msg, title, {
    easeTime: 1000
  });
};

我得到了以下错误:

Error: Uncaught (in promise): Error: NG0203: inject() must be called from an injection context (a constructor, a factory function or a field initializer)

好我以前try 使用支持函数获取路由参数时遇到了一个问题:

export const routeParam$ = (key: string) => {
  const activatedRoute = inject(ActivatedRoute);

  return activatedRoute.params.pipe(
    pluck(key),
    filter(r => r !== null),
    distinctUntilChanged()
  );
};

我只能在task: Observable<string> = routeParam$('task');的组件中用作字段初始值设定项

嗯，错误信息非常清楚...但仍然..我对angular14是新手，我想注射可以让我做到这一点.否则对我没什么用处.

现在我把它作为一种服务来移动..

import {Injectable} from '@angular/core';
import {ToastrService} from 'ngx-toastr';

@Injectable({
  providedIn: 'root'
})
export class MsgService {

  constructor(private toaster: ToastrService) {
  }

  public snackMsgSuccess = (msg: string, title?: string) => {
    this.toaster.success(msg, title, {
      easeTime: 1000
    });
  };


  public snackMsgInfo = (msg: string, title?: string) => {
    this.toaster.info(msg, title, {
      easeTime: 1000
    });
  };

  public snackMsgWarn = (msg: string, title?: string) => {
    this.toaster.warning(msg, title, {
      easeTime: 1000
    });
  };


  public snackMsgError = (msg: string, title?: string) => {
    this.toaster.error(msg, title, {
      easeTime: 1000
    });
  };
}

但这是实现它的唯一途径吗？甚至在angular14？