I have the following function, in order to update values from four different input fields:

let inputfieldtype = document.getElementById('selectPackageType');
let inputfieldweight = document.getElementById('floatWeight');
let inputfieldheight = document.getElementById('floatHeight');
let inputfielddescription = document.getElementById('description');

function updateValues(){
    var value = this.value;
    
      if (value == null) {
        console.log('value of packege is null');
      } else 
        
        if (value != "" && (inputfieldtype == 'selectPackageType')){
                  type = value; 
                          
              } else if (value != "" && (inputfieldweight == 'floatWeight')){
                  weight = value;
                  
              } else if (value != "" && (inputfieldheight == 'floatHeight')){
                  height = value;
                  
              } else if (value != "" && (inputfielddescription == 'description')){   
                  description = value;
                  
              }
         
     }  
 
        inputfieldweight.addEventListener('change', updateValues );
        inputfieldheight.addEventListener('change', updateValues);
        inputfielddescription.addEventListener('change', updateValues);
        inputfieldtype.addEventListener('change', updateValues);

what I learner so far is, that the condition of my if statement is not useful, because in all four cases, the string I want to compare it with, is true.
My goal is the following: I want to check, which input field has been clicked and I want to save the value of this field into a variable.

Then I want to create a new instance of my Class “Package” and fill their attributes with this values.

//Create instance of package
const package = new Package();
//shoot all the values into one package
function submit(){  
  if (typeof package != "undefined") {
      package.packageID = randomID;
      package.type = type;
      package.weight = weight; 
      package.height = height;
      package.description = description;   
      console.log(package);
  }else {
        console.log(package);
  }
}

Here is the HTML Code

<form autocomplete="off">
<div class="custom-select">
  <label for="selectPackageType">Type</label>
  <select id="selectPackageType" name ="type">
  
    <option value="1">letter</option>
    <option value="2" >package</option> 
  </select>
  </div>
</form>

<div class="fancy-input">
<label for="floatWeight">Weight</label>
<input id="floatWeight" name="floatWeight" maxlength ="8">
</div>

<div class="fancy-input">
<label for="floatHeight">Height</label>
<input id="floatHeight" name="floatHeight" maxlength ="8">
</div>

<div class="fancy-input">
<label for="description">Description</label>
<input id="description" name="description">
</div>

<button onclick="submit()">Submit</button>