[英]how to extract values from an object nested inside array inside object and store it in different arrays JAVASCRIPT
[英]How to extract values from an array of arrays in Javascript?
我有一個變量,如下所示:
var dataset = {
"towns": [
["Aladağ", "Adana", [35.4,37.5], [0]],
["Ceyhan", "Adana", [35.8,37], [0]],
["Feke", "Adana", [35.9,37.8], [0]]
]
};
該變量中包含許多城鎮數據。 如何有效地從數據中提取第三個元素? I,E,你會...
低於?
var myArray = ...
//myArray == [35.4,35.8,35.9] for the given data
如果要將兩個值都存儲在數組中怎么辦? 那是
var myArray = ...
//myArray == [[35.4,37.5], [35.8,37], [35.9,37.8]] for the given data
我是Java的新手。 我希望有一種不使用for循環的方法。
在較新的瀏覽器上,可以使用map
或forEach
,這樣可以避免使用for
循環。
var myArray = dataset.towns.map(function(town){
return town[2];
});
// myArray == [[35.4,37.5], [35.8,37], [35.9,37.8]]
但是for循環更兼容。
var myArray = [];
for(var i = 0, len = dataset.towns.length; i < len; i++){
myArray.push(dataset.towns[i][2];
}
不可能沒有循環:
var myArray = [];
for (var i = 0; i < dataset.towns.length; i++) {
myArray.push(dataset.towns[i][2][0]);
}
// at this stage myArray = [35.4, 35.8, 35.9]
如果要將兩個值都存儲在數組中怎么辦?
類似地,您只需添加整個數組,而不僅是第一個元素:
var myArray = [];
for (var i = 0; i < dataset.towns.length; i++) {
myArray.push(dataset.towns[i][2]);
}
// at this stage myArray = [[35.4,37.5], [35.8,37], [35.9,37.8]]
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.