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Javascript 对象属性为null,但输入的值不为null。如何正确插入值?_Javascript_Arrays_Oop_D3.js_Null - Fatal编程技术网

Javascript 对象属性为null,但输入的值不为null。如何正确插入值?

Javascript 对象属性为null,但输入的值不为null。如何正确插入值?,javascript,arrays,oop,d3.js,null,Javascript,Arrays,Oop,D3.js,Null,这是初始状态,我尝试在每个年份和每个速度之前添加year:和speed:属性,并将所有对象添加到数组中,以使用d3js进行处理 { 2004: "226.933" 2005: "222.807" 2006: "221.869" 2007: "223.978" 2008: "218.385" 2009: "217.668" 2010: "216.061" 2011: "214.631" 2012: "214.053" 2013: "213.845" 2014: "206.436" 2015: "2

这是初始状态,我尝试在每个年份和每个速度之前添加year:和speed:属性,并将所有对象添加到数组中,以使用d3js进行处理

{
2004: "226.933"
2005: "222.807"
2006: "221.869"
2007: "223.978"
2008: "218.385"
2009: "217.668"
2010: "216.061"
2011: "214.631"
2012: "214.053"
2013: "213.845"
2014: "206.436"
2015: "209.915"
2016: "214.51"
2017: "220.605"
2018: "222.128"
2019: "223.075"
}
创建对象数组的代码

let arr = [];
let columns = ["year","speed"]

Object.entries(results).forEach(element => {
      let imp = {};
      let x = parseInt(element)
      imp["year"] =parseInt(element[0]);
      imp["speed"]=parseFloat(element[1]);


      arr.push(imp);
});
console.log(arr);
这是我用控制台检查它时得到的结果

[
0: {year: null, speed: 226.933}
1: {year: null, speed: 222.807}
2: {year: null, speed: 221.869}
3: {year: null, speed: 223.978}
4: {year: null, speed: 218.385}
5: {year: null, speed: 217.668}
6: {year: null, speed: 216.061}
7: {year: null, speed: 214.631}
8: {year: null, speed: 214.053}
9: {year: null, speed: 213.845}
10: {year: null, speed: 206.436}
11: {year: null, speed: 209.915}
12: {year: null, speed: 214.51}
13: {year: null, speed: 220.605}
14: {year: null, speed: 222.128}
15: {year: null, speed: 223.075}
]
演示:

const结果={
2016: "214.51",
2017: "220.605",
2018: "222.128",
2019: "223.075",
}
设arr=[];
let列=[“年”,“速度”]
Object.entries(results).forEach(元素=>{
设imp={};
设x=parseInt(元素)
imp[“year”]=parseInt(元素[0]);
imp[“速度”]=parseFloat(元素[1]);
arr.push(imp);
});
控制台日志(arr)请尝试以下操作:-

var数据={
2004: "226.933",
2005: "222.807",
2006: "221.869",
2007: "223.978",
2008: "218.385",
2009: "217.668",
2010: "216.061",
2011: "214.631",
2012: "214.053",
2013: "213.845",
2014: "206.436",
2015: "209.915",
2016: "214.51",
2017: "220.605",
2018: "222.128",
2019: "223.075",
};
var newArray=[];
Object.entries(数据).map(函数(项){
推送({年:项[0],速度:项[1]})
})
console.log('data',data)
console.log('newArray',newArray)
试试这个:-

var数据={
2004: "226.933",
2005: "222.807",
2006: "221.869",
2007: "223.978",
2008: "218.385",
2009: "217.668",
2010: "216.061",
2011: "214.631",
2012: "214.053",
2013: "213.845",
2014: "206.436",
2015: "209.915",
2016: "214.51",
2017: "220.605",
2018: "222.128",
2019: "223.075",
};
var newArray=[];
Object.entries(数据).map(函数(项){
推送({年:项[0],速度:项[1]})
})
console.log('data',data)

log('newArray',newArray)
Sourav的一个很接近,但在
map
中不需要突变<代码>映射
返回一个新数组:

const数据={
2004: "226.933",
2005: "222.807",
2006: "221.869",
2007: "223.978",
2008: "218.385",
2009: "217.668",
2010: "216.061",
2011: "214.631",
2012: "214.053",
2013: "213.845",
2014: "206.436",
2015: "209.915",
2016: "214.51",
2017: "220.605",
2018: "222.128",
2019: "223.075",
};
const newArray=Object.entries(数据)
.map(([year,speed])=>({year,speed}))
console.log('data',data)

log('newArray',newArray)
Sourav的一个很接近,但在
map
中不需要突变<代码>映射返回一个新数组:

const数据={
2004: "226.933",
2005: "222.807",
2006: "221.869",
2007: "223.978",
2008: "218.385",
2009: "217.668",
2010: "216.061",
2011: "214.631",
2012: "214.053",
2013: "213.845",
2014: "206.436",
2015: "209.915",
2016: "214.51",
2017: "220.605",
2018: "222.128",
2019: "223.075",
};
const newArray=Object.entries(数据)
.map(([year,speed])=>({year,speed}))
console.log('data',data)

console.log('newArray',newArray)
考虑
map
而不是
forEach
。演示似乎工作正常。代码正常,只有json无效,没有
考虑
map
而不是
forEach
。演示似乎工作正常。代码正常,只有json无效,没有