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Arrays *按项目数量列出的循环_Arrays_Angular_Angular8 - Fatal编程技术网

Arrays *按项目数量列出的循环

Arrays *按项目数量列出的循环,arrays,angular,angular8,Arrays,Angular,Angular8,我有项目数组 [ { "Name": "Bread", "Price": 10, "quantity": 4 }, { "Name": "Jam", "Price": 2, "quantity": 0 }, { "Name": "Butter", "Price": 5, "quantity": 1 }, ... ] *ngFor=“let item of items”循环项目一次,但我希望它按数量循环每个

我有项目数组

[
  {
    "Name": "Bread",
    "Price": 10,
    "quantity": 4
  },
{
    "Name": "Jam",
    "Price": 2,
    "quantity": 0
  },
  {
   "Name": "Butter",
    "Price": 5,
    "quantity": 1
  },
...
]

*ngFor=“let item of items”循环项目一次,但我希望它按数量循环每个项目,也就是说,“面包”应该循环4次,而果酱不应该出现在循环中。

在javascript中创建新数组更好、更简单:

items = [ ... ];
itemQuantities = [];

ngOnInit(): void {
  this.items.forEach(item => {
    for (let i = 0; i < item.quantity; i++) {
      itemQuantities.push(item);
    }
  });
}
items=[…];
项目数量=[];
ngOnInit():void{
this.items.forEach(item=>{
for(设i=0;i
您尝试了什么,到底有什么问题?我已经更新了我的答案,以说明您的问题所在。