ha_permissions/ui/adminCreate/index.js

export default {
    form: null,

    display(){
        if(this.form === null){
            this.form = document.querySelector("#adminCreatePage form");
            this.form.addEventListener("submit", (event)=>{
                this.submit(event);
            });
        }

        document.getElementById("adminCreateName").focus();
    },

    submit(event){
        event.preventDefault();

        const data = {
            name: document.getElementById("adminCreateName").value,
            email: document.getElementById("adminCreateEmail").value,
            password: document.getElementById("adminCreatePass").value,
            confirm_password: document.getElementById("adminCreatePassConf").value
        };
        console.log(data);
    }
}