Create a sample HTML select of taxonomy terms

Question

I created a custom form in a custom module. (in a class that extends FormBase) I want to add a (very) simple html select element, this select must contains all taxonomy elements of a specific vocabulary, like this, where the integers are the taxonomy term IDs.

<select id="...>
    <option value="4">tutu</option>
    <option value="15">toto</option>
    <option value="61">tata</option>
    ...
    <option value="48">titi</option>
</select>

How can I create this <select> tag using the taxonomy term ID and the taxonomy term name? The users would not see the taxonomy term ID, but only the taxonomy term name.

With a vocabulary name, how can I generate the good structure (an array?) that allows me create the <select> tag?

Answer 1

You will need to get your terms (with a query or load the vocab), loop over them and create an array of term tid and term label. Set that array as the #options property on the select field in your form code.