javascript - How to convert string JSON data in the applet to Number type

Question

/** index.js*/
var app = getApp()  
Page({  
    data: {  
        /**   
         * 页面配置  
         */  
        winWidth: 0,  
        winHeight: 0,  
        // tab切换    
        currentTab: 0, 
                option1:[
          {value:"1",contant:"A:xxxx"},
          {value:"2",contant:"B:xxxx"},
          {value:"3",contant:"C:xxxx"},
          {value:"4",contant:"D:xxxx"}
        ],
        option2: [
          { value: "1", contant: "A:xxxx" },
          { value: "2", contant: "B:xxxx" },
          { value: "3", contant: "C:xxxx" },
          { value: "4", contant: "D:xxxx" }
        ], 
        option3: [
          { value: "1", contant: "A:xxxx" },
          { value: "2", contant: "B:xxxx" },
          { value: "3", contant: "C:xxxx" },
          { value: "4", contant: "D:xxxx" }
        ],
        option1Value:0,
        option2Value:0,
        option3Value:0,
    },  
    onLoad: function() {   swiperChange: function(e){
                var that = this;
        if(that.data.currentTab==0){
          that.setData({
            option1Value : e.detail.value,
            currentTab: 1 
          });
        }else if(that.data.currentTab==1){
          that.setData({
            option2Value : e.detail.value,
            currentTab: 2
          });
        }else if(that.data.currentTab==2){
          that.setData({
            option3Value : e.detail.value,
            currentTab: 3
          })
        } 
         }   


})  

<!-- index.wxml -->
                    <!-- 问题区域 -->
<view class="swiper-tab">    
    <view class="swiper-tab-list {{currentTab==0 ? 'on' : ''}}" data-current="0" bindtap="swichNav">第一题</view>    
    <view class="swiper-tab-list {{currentTab==1 ? 'on' : ''}}" data-current="1" bindtap="swichNav">第二题</view>    
    <view class="swiper-tab-list {{currentTab==2 ? 'on' : ''}}" data-current="2" bindtap="swichNav">第三题</view>      
</view>

                    <!-- 选项区域 -->
<swiper current="{{currentTab}}" class="swiper-box" duration="300" style="height:{{winHeight - 31}}px" bindchange="bindChange">    

                    <!-- 第一题选项 -->    
    <swiper-item>    
      <radio-group bindchange="swiperChange">
        <label class="option" wx:for="{{option1}}">
          <radio value="{{item.value}}" />{{item.contant}}
        </label>
      </radio-group>   
    </swiper-item>    

                    <!-- 第二题选项 -->    
    <swiper-item>    
      <radio-group bindchange="swiperChange">
        <label class="option" wx:for="{{option2}}">
          <radio value="{{item.value}}" />{{item.contant}}
        </label>
      </radio-group>   
    </swiper-item>  

                    <!-- 第三题选项 -->    
    <swiper-item>    
      <radio-group bindchange="swiperChange">
        <label class="option" wx:for="{{option3}}">
          <radio value="{{item.value}}" />{{item.contant}}
        </label>
      </radio-group>   
    </swiper-item> 

     <swiper-item>    
        <view>{{score}}</view>
    </swiper-item>

The above is my code. I want to realize that there are three questions on the page, each with four options with different scores. The results will pop up directly after the user selects. However, the JSON data that stores the options selected by the user is a string. How to convert it? For numeric type?

Answer 1

e.detail.value - 0

Answer 2

When you save it, it is a number, and when it is parsed, it is a number...
Now you are saving a string..
If you want to convert it, just
+e.detail.value will do