如何通过ID ngrx获取实体

npm install @ngrx/entity

import { createEntityAdapter, EntityAdapter, EntityState } from '@ngrx/entity';

export interface Product {
  id: number;
  name: string;
  price: number;
}

export interface ProductsState extends EntityState<Product> {}

export const productAdapter: EntityAdapter<Product> = createEntityAdapter<Product>();

export const initialState: ProductsState = productAdapter.getInitialState();

import { productAdapter } from './product.reducer';

export function productsReducer(state = initialState, action: any): ProductsState {
  switch (action.type) {
    case 'ADD_PRODUCT':
      return productAdapter.addOne(action.product, state);
    // ...其他操作
    default:
      return state;
  }
}

import { createSelector } from '@ngrx/store';
import { ProductsState } from './product.reducer';

export const selectProductsState = (state: any) => state.products;

export const selectProductById = (id: number) =>
  createSelector(
    selectProductsState,
    (productsState: ProductsState) => productsState.entities[id]
  );

import { Component } from '@angular/core';
import { Store } from '@ngrx/store';
import { selectProductById } from './product.selectors';

@Component({
  selector: 'app-product-detail',
  template: `<div *ngIf="product">{{ product | json }}</div>`
})
export class ProductDetailComponent {
  product$ = this.store.select(selectProductById(1)); // 假设你想获取ID为1的产品

  constructor(private store: Store) {}
}