Looping jsom getItems

Question

I want to make a function to get data from SP list thru jsom, when i run the function with multiple items I get the error, with only one item it does work correct.

Error:

Uncaught Error: The collection was not initialized. The initialization is not requested or the application is not running. Possibly the initialisation must be made explicit.

My code: (error comes up when run go and fails on this.collListItem.getEnumerator();)

function go() {
  for (var i = 0; i < 5; i++) {
    getEmployee2(i);            
  }
}

function getData(number) {
  var clientContext = new SP.ClientContext(theSite);
  var oList = clientContext.get_web().get_lists().getById(emplist);

  var camlQuery = new SP.CamlQuery();
  camlQuery.set_viewXml('<View><Query><Where><Eq><FieldRef Name="Number"/><Value Type="Text">' + number + '</Value></Eq></Where></Query></View>');
  this.collListItem = oList.getItems(camlQuery);

  clientContext.load(collListItem);
  clientContext.executeQueryAsync(Function.createDelegate(this, this.onQuerySucceeded), Function.createDelegate(this, this.onQueryFailed));
}

function onQuerySucceeded() 
{
  var listItemInfo = '';
  var listItemEnumerator = this.collListItem.getEnumerator();

  while (listItemEnumerator.moveNext()) {
    var oListItem = listItemEnumerator.get_current();
    console.log('emp' + oListItem.get_id());
  }
}

function onQueryFailed() {
  alert('fail');
}

How can I solve this? I doesn't matter if it's runs sync or async. I think collListItem is used multiple times giving the error?

Answer 1

Your problem is scope, solving it by creating globals isn't considered good practice.

So pass the payload to your functions:

with: processItems.bind(request)

function getItems(listName,siteUrl){
    var request={};
    request.listName=listName;
    request.siteUrl=siteUrl || _spPageContextInfo.siteAbsoluteUrl;
    var ctx = new SP.ClientContext(request.siteUrl);
    var list = ctx.get_web().get_lists().getByTitle(request.listName);
    request.query=SP.CamlQuery.createAllItemsQuery();
    request.itemCollection=list.getItems(request.query);
    ctx.load(request.itemCollection);
    ctx.executeQueryAsync(  processItems.bind(request)  ,failure);
}
function processItems() {
    var received=this;//received 'request' from Caller
    received.items=[];
    var listEnumerator = received.itemCollection.getEnumerator();
    while (listEnumerator.moveNext()) {
        var listitem = listEnumerator.get_current();
        received.items.push(listitem.get_id());
    }
    console.info(received.listName,'has',received.items.length,'items IDs:',received.items);
}
function failure(sender, args){
    console.error(args.get_message());
}
console.clear();
for(var cycle=1;cycle<4;cycle++){// call multiple times to show ASYNC result in the console
    console.log('Calling 3 lists cycle:',cycle);
    getItems('Tasks');
    getItems('Documents');
    getItems('Images');
}

You could have bound just the itemCollection itself, but I elaborated a bit to show how to pass more data.

For (oldschool) CreateDelegate and (since ES-5) bind() differences see: Differing ways to make executeQueryAsync calls - Function.createDelegate (is old IE8 code)

Run this and you will see the asynchronous responses:
(Tasks was requested first, but Documents was received first, etc)

J1 J5 iBind

Answer 2

Please try to declare "collListItem" globally.

Please refer below updated code and let me know if face any problem.

function go() {
  for (var i = 0; i < 5; i++) {
    getEmployee2(i);            
  }
}

var collListItem = "";
function getData(number) {
  var clientContext = new SP.ClientContext(theSite);
  var oList = clientContext.get_web().get_lists().getById(emplist);

  var camlQuery = new SP.CamlQuery();
  camlQuery.set_viewXml('<View><Query><Where><Eq><FieldRef Name="Number"/><Value Type="Text">' + number + '</Value></Eq></Where></Query></View>');
  collListItem = oList.getItems(camlQuery);

  clientContext.load(collListItem);
  clientContext.executeQueryAsync(Function.createDelegate(this, this.onQuerySucceeded), Function.createDelegate(this, this.onQueryFailed));
}

function onQuerySucceeded() 
{
  var listItemInfo = '';
  var listItemEnumerator = collListItem.getEnumerator();

  while (listItemEnumerator.moveNext()) {
    var oListItem = listItemEnumerator.get_current();
    console.log('emp' + oListItem.get_id());
  }
}

function onQueryFailed() {
  alert('fail');
}