匹配 JavaScript 中另一个数组的对应值后，如何根据一个数组中的值提取数据？

Question

This is the URL from GeoServer to get feature info

{"type":"FeatureCollection","features":[{"type":"Feature","id":"weather_warning_day_1.fid--418ec0da_178b69d5dfc_-715c","geometry":null,"properties":{"issue_date":"2021-04-09","updated_at":"2021-04-09T09:26:33+05:30","utc_time":0,"state_name":"Odisha","state_id":21,"district_name":"MAYURBHANJ","district_id":232,"api_district_name":"MAYURBHANJ","day_1":"6,9,10","day1_color":3}}],"totalFeatures":"unknown","numberReturned":1,"timeStamp":"2021-04-09T15:38:19.536Z","crs":null}

the data I want to extract is of variable: "day_1":"6,9,10" which I got from the layer and stored it in the variable as

var warning_day_1 = weather_warning_layer_data.features[0].properties.day_1

so basically the input is "day_1":"6,9,10" which I have stored in the array as

[{"warning":"6"},{"warning":"9"},{"warning":"10"}]

and corresponding output should be Dust Storm, Heat Wave, Hot Day

Dust Storm, Heat Wave, Hot Day

or if the input was "day_1":"2,5" then output should have been Heavy Rain, Hailstorm

or if the input was "day_1":"1" then output should have been No Warning

After reading the data of the string and creating its array, I have to compare it with another array and extract the key values (display) corresponding to the key values (warning) in the 1st array.

var warning_data_split = warning_day_1.split(/[ ,]+/);
var warning_data_from_api_array = new Array;
warning_data_from_api_array.push(warning_data_split);


for (var i = 0; i < warning_data_from_api_array.length; i++) {
var item_in_array_to_compare = warning_data_from_api_array[i];
if(warning_data_from_api_array[item_in_array_to_compare.warning_data_from_api_array])
{warning_data_from_api_array[item_in_array_to_compare.warning_data_from_api_array].push(item_in_array_to_compare);} 
else {
warning_data_from_api_array[item_in_array_to_compare.warning_data_from_api_array] = [item_in_array_to_compare];}}

let final_array_to_compare = item_in_array_to_compare
final_array_to_compare = final_array_to_compare.map(x => ({warning: x})); 
/// this is the first array ////////////

The values in this array are not static in length, as it keeps on changing like, sometimes the array has value [1] or [1,2], [2,5,8], [4,7,12], etc so I have to extract the corresponding values of display from the lookup array given below

var warning_code_meaning_list = [
{ warning:"1", display:"No Warning"}, 
{ warning:"2", display:"Heavy Rain"}, 
{ warning:"3", display:"Heavy Snow"}, 
{ warning:"4", display:"Thunderstorm & Lightning, Squall etc"},  
{ warning:"5", display:"Hailstorm"},
{ warning:"6", display:"Dust Storm"},
{ warning:"7", display:"Dust Raising Winds"},
{ warning:"8", display:"Strong Surface Winds"},
{ warning:"9", display:"Heat Wave"},
{ warning:"10", display:"Hot Day"},
{ warning:"11", display:"Warm Night"},
{ warning:"12", display:"Cold Wave"},
{ warning:"13", display:"Cold Day"},
{ warning:"14", display:"Ground Frost"},
{ warning:"15", display:"Fog"}
]

The data which I am getting in warning_day_1 (in the very first line of the code) is a string (this couldn't be saved as float/integer in the database column because sometimes there are more than 1 warning for a specific place, so I have stored this as a text in the database) Which I'm converting to an array after reading it from the API

Now this string, which I am fetching from API has variable data, Some time single digit like: 1 Sometime multiple: 1,2,3

And each of the integer present in this array corresponds to the specific text shown in the next array like if the warning is 2 it means the heavy rainfall, but if the string (later converted to an array, with “warning” as a key) has 2,5 as value, it means: heavy rainfall & Hailstorm

I want that the values which come up in array 1 (the dynamic one) got match with the 2nd array ( a sort of lookup array) and fetch its display value as output.

How to do so?

Answer 1

You could use an object to map your warnings to messages.

Try this:

const data = {"type":"FeatureCollection","features":[{"type":"Feature","id":"weather_warning_day_1.fid--418ec0da_178b69d5dfc_-715c","geometry":null,"properties":{"issue_date":"2021-04-09","updated_at":"2021-04-09T09:26:33+05:30","utc_time":0,"state_name":"Odisha","state_id":21,"district_name":"MAYURBHANJ","district_id":232,"api_district_name":"MAYURBHANJ","day_1":"6,9,10","day1_color":3}}],"totalFeatures":"unknown","numberReturned":1,"timeStamp":"2021-04-09T15:38:19.536Z","crs":null}
var warning_code_meaning_list = {
  "1":"No Warning",
  "2":"Heavy Rain",
  "3":"Heavy Snow",
  "4":"Thunderstorm & Lightning, Squall etc", 
  "5":"Hailstorm",
  "6":"Dust Storm",
  "7":"Dust Raising Winds",
  "8":"Strong Surface Winds",
  "9":"Heat Wave",
  "10":"Hot Day",
  "11":"Warm Night",
  "12":"Cold Wave",
  "13":"Cold Day",
  "14":"Ground Frost",
  "15":"Fog",
};

results = data["features"].map(feature => {
  return feature.properties.day_1.split(',').map(code => {
    return warning_code_meaning_list[code];
  });
});

That gives you an array of arrays of the displays:

[ [ 'Dust Storm', 'Heat Wave', 'Hot Day' ] ]