JavaScript的数组二维数组

Question

我有一个JavaScript数组这样

var myArr = [ 

    { 
     "Year":"2015", 
     "Month":"January", 
     "Value":"15.8", 
     "District":"Anuradhapura", 
     "type":"Rainfall" 
    }, 
    { 
     "Year":"2015", 
     "Month":"January", 
     "Value":"31.1", 
     "District":"Anuradhapura", 
     "type":"Temparature" 
    }, 
    { 
     "Year":"2015", 
     "Month":"January", 
     "Value":"4", 
     "District":"Anuradhapura", 
     "type":"Wind" 
    }, 
    { 
     "Year":"2015", 
     "Month":"January", 
     "Value":"69", 
     "District":"Anuradhapura", 
     "type":"Humidity" 
    } 
] 

我需要的是把type和Value数据为2维数组。我的最终结果应该是这样的;

var data = [ 
     [ 
      "Rainfall", 
      158 
     ], 
     [ 
      "Temparature", 
      31.1 
     ], 
     [ 
      "Wind", 
      4 
     ], 
     [ 
      "Humidity", 
      69 
     ] 
    ] 

注意myArr结果我从后端服务，该数组的长度让我可以动态改变。我怎样才能做到这一点。感谢

Answer 1

试试这个：

随着foreach功能

文档：Array.forEach

var data = []; 

myArr.forEach(x => data.push([x.type, parseFloat(x.Value)])) 

随着map功能

文档：Array.Map

var data = myArr.map(x => [x.type, parseFloat(x.Value)]); 

Answer 2

可以简单地使用Array.map功能对象阵列映射到二维阵列。

var data = myArr.map(function(o){ 
     return [o.type, o.Value] 
    }); 

此外，如果你想要的值转换成float数字代替string，与pasreFloat

var data = myArr.map(function(o){ 
     return [o.type, pasreFloat(o.Value)] 
    }); 

Answer 3

为此，您可以使用Arrays.map函数来得到结果：

 var data = myArr.map(function(input){ return [input.type, input.Value]; }); 

这个函数会将数组中的每个元素转换为另一个元素，因为你需要一个数组数组，你的mappin g函数必须从一个对象中创建一个数组。

Answer 4

let data = []; 
myArr.map(a => { 

data.push([a.type, a.Value]); 

}); 

Answer 5

我熟悉underscore.js：你可以使用：

_.zip(_.pluck(myArr, "type"), _.pluck(myArr, "Value")); 

var myArr = [ 
 

 
    { 
 
     "Year":"2015", 
 
     "Month":"January", 
 
     "Value":"15.8", 
 
     "District":"Anuradhapura", 
 
     "type":"Rainfall" 
 
    }, 
 
    { 
 
     "Year":"2015", 
 
     "Month":"January", 
 
     "Value":"31.1", 
 
     "District":"Anuradhapura", 
 
     "type":"Temparature" 
 
    }, 
 
    { 
 
     "Year":"2015", 
 
     "Month":"January", 
 
     "Value":"4", 
 
     "District":"Anuradhapura", 
 
     "type":"Wind" 
 
    }, 
 
    { 
 
     "Year":"2015", 
 
     "Month":"January", 
 
     "Value":"69", 
 
     "District":"Anuradhapura", 
 
     "type":"Humidity" 
 
    } 
 
]; 
 

 

 
alert(JSON.stringify(_.zip(_.pluck(myArr, "type"), _.pluck(myArr, "Value"))));

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