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Javascript 不改变道具的双循环,VUE3_Javascript_Vue.js_Map Function_Vue Props - Fatal编程技术网

Javascript 不改变道具的双循环,VUE3

Javascript 不改变道具的双循环,VUE3,javascript,vue.js,map-function,vue-props,Javascript,Vue.js,Map Function,Vue Props,我有一个“数据”道具,上面写着: data = [ { "label":"gender", "options":[ {"text":"m","value":0}, {"text":"f","value":1}, {"text&qu

我有一个“数据”道具,上面写着:

data = [
    {
      "label":"gender",
      "options":[
        {"text":"m","value":0},
        {"text":"f","value":1},
        {"text":"x", "value":null}
      ]
    },
    {
      "label":"age",
      "options":[
        {"text":"<30", "value":0},
        {"text":"<50","value":1},
        {"text":">50","value":3}
      ]
    }
  ]
data.forEach(item => {
    item.options.forEach(option => {
      if (option.value !== null && option.value !== 0) {
        option.value *= 2;
      }
    })
  });
现在我尝试在一个computed属性中使用.map()来实现这一点,这样它就不会改变我的数据道具,但我不知道如何实现

computed: {
  doubledValues() {
    var array = this.data.map((item) => {
      //...
      item.options.map((option) => {
        //... option.value * 2;
      });
    });
    return array;
  }
}

只需复制对象/数组。会是这样的

computed: {
  doubledValues() {
    return this.data.map((item) => {
      const resultItem = {...item};
      resultItem.options = item.options.map((option) => {
        const copyOption = {...option};
        if (copyOption.value !== null && copyOption.value !== 0) {
          copyOption.value *= 2;
        }
        return copyOption;
      });
      return resultItem;
    });
  }
}
您可以使用
map()
方法,如下所示:

计算:{
双值(){
返回this.data.map(item=>({…item,options:item.options.map(obj=>{
返回(obj.value!=null)?{…obj,value:obj.value*2}:{…obj}
})})
);
}
}