1. 在组件中使用数组过滤器，根据“category”属性值和最低价格过滤数组对象。比如：

this.items = [
  {name: 'item1', price: 10, category: 'category1'},
  {name: 'item2', price: 20, category: 'category1'},
  {name: 'item3', price: 15, category: 'category2'},
  {name: 'item4', price: 5, category: 'category3'},
  {name: 'item5', price: 12, category: 'category3'},
  {name: 'item6', price: 8, category: 'category3'}
];

this.uniqueCategories = [...new Set(this.items.map(item => item.category))];
this.filteredItems = this.uniqueCategories.map(category => {
  return this.items.filter(item => item.category === category)
    .sort((a, b) => a.price - b.price)
    .reduce((acc, cur) => acc.price < cur.price ? acc : cur);
});

2. 在模板中使用 *ngFor 指令循环遍历过滤后的数组对象，并显示最低价格。比如：

  
{{item.category}}
  
{{item.price}}