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从特定的json字段提取数据,将其用作变量,并更新字段值?

geolocation node.js json arrays javascript

-1

pploypiti · 技术社区 · 7 年前

我需要将origin值更改为lat/lang坐标(来自另一个geojson文件),而不是country name:

index = [
  {
    "Name": "Aish Merahrah",
    "Origin": "Egypt",
    "Description": "Made with fenugreek seeds and maize; dough allowed to 
ferment overnight, then flattened and baked."
  },
  {
    "Name": "Ajdov Kruh",
    "Origin": "Slovenia",
    "Description": "Made with buckwheat flour and potato."
  }
]

结果会是:

  {
    "Name": "Ajdov Kruh",
    "Origin": "46.151241, 14.995463",
    "Description": "Made with buckwheat flour and potato."
  }

我不确定工作流程,是否需要提取json值变量并以某种方式使用该变量来获取lat&lang数据?顺便说一句需要只使用js/jquery和node。

3 回复 | 直到 7 年前

kiddorails 7 年前

假设您的geojson具有以下结构(country name作为key,lat/long作为value):

geolocation = {"Slovenia": "46.151241, 14.995463", "Egypt": "1, 1"}

你可以使用 Array.prototype.map 迭代 index 以及替换 Origin 每个对象的值 geolcoation .

index = [
  {
    "Name": "Aish Merahrah",
    "Origin": "Egypt",
    "Description": "Made with fenugreek seeds and maize; dough allowed to ferment overnight, then flattened and baked."
  },
  {
    "Name": "Ajdov Kruh",
    "Origin": "Slovenia",
    "Description": "Made with buckwheat flour and potato."
  }
]
geolocation = {"Slovenia": "46.151241, 14.995463", "Egypt": "1, 1"};
result = index.map(function(obj) { obj['Origin'] = geolocation[obj['Origin']]; return obj }); 
console.log(result);

你甚至可以使用 forEach 若要在上面迭代,它仍将更改 指数 ,因为更改是在引用对象中完成的。

Nikhil Aggarwal 7 年前

使用 Array.forEach

let index = [{"Name":"Aish Merahrah","Origin":"Egypt","Description":"Made with fenugreek seeds and maize; dough allowed to ferment overnight, then flattened and baked."},{"Name":"Ajdov Kruh","Origin":"Slovenia","Description":"Made with buckwheat flour and potato."}];
let lat = {"Slovenia": "46.151241, 14.995463", "Egypt": "26.820553, 30.802498"};
index.forEach(o => o.Origin = lat[o.Origin] ?  lat[o.Origin] :  o.Origin); 
console.log(index);

Alex 7 年前

只需遍历对象索引,然后用值编辑值。

假设给定的json数据:

// Creates an Object
let index = [
  {
    "Name": "Aish Merahrah",
    "Origin": "Egypt",
    "Description": "Made with fenugreek seeds and maize; dough allowed to ferment overnight, then flattened and baked."
  },
  {
    "Name": "Ajdov Kruh",
    "Origin": "Slovenia",
    "Description": "Made with buckwheat flour and potato."
  }
]

console.log(`Original Origin 1: ${index[0].Origin}\nOriginal Origin 2: ${index[1].Origin}`);

// Iterate over indices
for(let i=0;i<index.length;i++) {
  // Edit the value
  index[i].Origin = "1234/1234"
}

/*
// Using forEach
index.forEach((elem) => {
  elem.Origin = "Your Value";
});
*/

console.log(`Edited Origin 1: ${index[0].Origin}\nEdited Origin 2: ${index[1].Origin}`);