在Typescript中过滤嵌套数组对象的数组

Question

我在过滤嵌套数组数据集时遇到了一些麻烦。例如我下面有数据数组的列表：

let list = [
{
  "percentage": 50.0,
  "budget": "online",
  "ruleName": "C1"
},
{
  "percentage": 50.0,
  "budget": "offline",
  "ruleName": "C1"
},
{
  "percentage": 50.0,
  "budget": "other",
  "ruleName": "C4"
}

]

现在，我想使用.map或.filter并考虑以下条件来实现以下结果：如果父数组和子组数组的budget属性匹配，则它应仅返回组内匹配的对象，而不返回所有对象：

[
  {
    "budget": "online",
    "ruleName": "C1",
    "group": [
        {
            "budget": "onlne",
            "percentage": 50.0
        }
    ]
  },

  {
    "budget": "offline",
    "ruleName": "C1",
    "group": [
        {
            "budget": "offline",
            "percentage": 50.0
        }
    ]
  },

  {
    "budget": "other",
    "ruleName": "C4",
    "group": [
        {
            "budget": "other",
            "percentage": 0
        }
    ]
  }

]

所以我执行了以下操作，但结果与上面的预期结果不符：

this.group = list.map((i)=>{
  return {
    budget: i.budget,
  }
})
this.payments = list.map((i)=>{
  return {
    budget: i.budget,
    amtPercentage: i.percentage ? i.percentage : 0,
    rulename: i.rulename,
    group: this.group
  }
})

以上代码执行后，结果如下：

[
{
    "budget": "online",
    "ruleName": "C1",
    "group": [
        {
            "budget": "onlne",
            "percentage": 50.0
        },
        {
            "budget": "offline",
            "percentage": 50.0
        },
        {
            "budget": "other",
            "percentage": 0
        }
    ]
},

{
    "budget": "offline",
    "ruleName": "C1",
    "group": [
        {
            "budget": "onlne",
            "percentage": 50.0
        },
        {
            "budget": "offline",
            "percentage": 50.0
        },
        {
            "budget": "other",
            "percentage": 0
        }
    ]
},

{
    "budget": "other",
    "ruleName": "C4",
    "group": [
        {
            "budget": "onlne",
            "percentage": 50.0
        },
        {
            "budget": "offline",
            "percentage": 50.0
        },
        {
            "budget": "other",
            "percentage": 0
        }
    ]
}

]

我没有任何线索可以根据以下条件来过滤嵌套的组数组：如果父数组budget属性等于group.budget属性，则它应该仅返回该对象，而不返回所有对象。

谢谢您的帮助。提前谢谢了。

注意：我正在使用带有angular-2的打字稿。

Answer 1

this.payments = list.map((i)=>{
  return {
    budget: i.budget,
    amtPercentage: i.percentage ? i.percentage : 0,
    rulename: i.rulename,
    group: this.group.filter((x) => i.budget === x.budget)
  }
})