javascript - 分配字符串的变量值

Question

我是 Javascript 新手 - 我尝试在网络上搜索但无法将这种情况融入上下文。

情况如下:

import * as People from ./People.json
import * as Education from ./Education.json
import * as Vehicle from ./Vehicle.json
...
function transpose(str : string) {
  let data = {};
  if(validate(str))  //validate function returns true if valid string
    data = str  //data takes in the string value and uses variable name
    runFile(data); //runFile expects data to be a JSON type
  ...
}

本质上，如果假设 str = "People" 那么数据将等于变量 People 或者如果 str = “Vehicle” 数据将是 Vehicle 变量。

我知道这可以通过{“People”:People，“Vehicle”:Vehicle}的 map 来完成，似乎应该有更好的方法？我还研究了 eval(str) 但这似乎并没有解决问题。

如有任何帮助，我们将不胜感激。

谢谢

Answer 1

“ map ”确实是最好的方法。好消息是，您可以使用简写属性名称来保存一些击键 (ES2015):

import * as People from ./People.json
import * as Education from ./Education.json
import * as Vehicle from ./Vehicle.json

const lookup = {People,Education,Vehicle}; // equivalent to {"People":People, ...}

function transpose(str : string) {
  let data = {};
  if(validate(str))  //validate function returns true if valid string
    data = lookup[str]  //data takes in the string value and uses variable name
    runFile(data); //runFile expects data to be a JSON type
  ...
}