如何在发送到API之前使用输入字段中的值从UI动态创建json对象

var searchQuery = "";
var subj = null;
var body = "";
var startDate = "";
var endDate = null;

let obj = {
  "search": {
    "scope": [2, 3, 32],
    "type": "basic",
    "text": {
      "value": searchQuery, //string variable coming from UI
      "fields": [
        subj, body //string variable coming from UI
      ]
    },

    "date": {
      "type": "range",
      "from": startDate, //string variable coming from UI
      "to": endDate //string variable coming from UI
    }
  }
}

function removeNull(obj) {
  return Object.keys(obj).reduce((res, key) => {
    if (Array.isArray(obj[key])) {
      // If it's an array, filter out the null items
      res[key] = obj[key].filter((item) => item != null && item !== "");
    } else if (typeof obj[key] === "object" && obj[key] != null) {
      // If it's an object, call the function recursively
      res[key] = removeNull(obj[key]);
    } else if (obj[key] != null && obj[key] !== "") {
      // Otherwise, only add it to the results if it's not null
      res[key] = obj[key];
    }
    return res;
  }, {});
}

console.log(removeNull(obj));