打字稿：遍历下拉列表

Question

I am new to Typescript and I have a dropdown whose values I need to iterate through. This is the code I am trying:

var sortBy = document.getElementById("SortbySel");

I want to iterate through the options but since this is an HTMLElement, I am unable to do so. What would be the best way to do this?

Answer 1

One way would be to use the querySelectorAll function:

var options = document.querySelectorAll('#SortbySel option');
for(var i = 0; i < options.length; i++){
    console.log(options.item(i).value);
}

Answer 2

Check out this stackblitz POC where I iterated over select HTML element

If you are using typescript it is always better to use specific classes like HTMLSelectElement & HTMLOptionElement instead of using conventional var declarations as it helps a lot in intellisense.

the code looks like this -

let selectElement: HTMLSelectElement = 
document.getElementById('select') as HTMLSelectElement;

for (let i = 0; i < selectElement.options.length; i++) {
  let option: HTMLOptionElement = selectElement.options[i];
  console.log(option);
}