how to get people picker user ID with javascript

Question

I just created a custom edit form for a list in SP Designer from a task list, i created 3 more taskoutcome options and a button for each option, one of them only edit the assigned to field and update the list for CSOM, the problem is that I couldnt get the user ID for the person picker with JavaScript to send an update to the task list.

In dev tools all the info appear in a div with a data attributte ArrayOfDictionaryEntry where the user id appears, I just tried to retrieve it like this:

//only dataset because is <div data="info">
getElementsByTagName("DIV").dataset

how can I get the user id from the person picker to send an update to list?

Answer 1

I found the answer, gettin the attribute description on div#divEntityData that return the info domain\user and sending to currentUser.get_id(); as bellow

function getUser(user){
      var clientContext = new SP.ClientContext.get_current();
    var website = clientContext.get_web();
    currentUser = website.ensureUser(user);
    clientContext.load(website);
    clientContext.load(currentUser);
    clientContext.executeQueryAsync(onRequestSucceeded, onRequestFailed);
}


    function onRequestSucceeded() {
       var userid =  currentUser.get_id();

finally the userid send to update the assignedTo field like this

function updateItem(taskoutcome,idUser) {
   var clientContext = new SP.ClientContext.get_current();
   var oList = clientContext.get_web().get_lists().getByTitle('TaskList');
   this.oListItem = oList.getItemById(QueryString.ID);
   oListItem.set_item('TaskOutcome', taskoutcome);
   oListItem.set_item('AssignedTo', idUser);

   oListItem.update();              
   clientContext.executeQueryAsync(Function.createDelegate(this, this.onQuerySucceeded), Function.createDelegate(this, this.onQueryFailed));
}