1

I need to alter fields if 4 lists when a button is pressed. I've created a single CSOM (javascript) block code that I pass a parameter to. This being ID of item and the ListName.

Then I call the functions :

<input name="Submit1" type="button" value="LockItems"  onclick='LockItems()'/>

function LockItems()
{
lockListItems(tID,'List1');
lockListItems(tID,'List2');
lockListItems(tID,'List3');
lockListItems(tID,'List4');
}

There is no order required as long as they all execute. However If I wanted to alert after the final code block has executed how do I accomlish this as code runs asyncrounously?

I guess I could repeat the block 4 times and nest in the OnSuccess but this is repeating code. Can the next function be called only when the previous function has been confirmed ?

function lockListItems(tID,varList) {

    var clientContext = new SP.ClientContext.get_current();
    var oList = clientContext.get_web().get_lists().getByTitle(varList);

    var camlQuery = new SP.CamlQuery();
    camlQuery.set_viewXml('<View><Query><Where><Eq><FieldRef Name=\'TeamRequest\'/>' + 
        '<Value Type=\'Number\'>'+ tID +'</Value></Eq></Where></Query></View>');
    this.collListItem = oList.getItems(camlQuery);
     this.varList = varList; // add varList so able to pass into next function

    clientContext.load(collListItem);

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

}

function onQuerySucceeded(sender, args) {


    var listItemInfo = '';

    var listItemEnumerator = collListItem.getEnumerator();


    while (listItemEnumerator.moveNext()) {
        var oListItem = listItemEnumerator.get_current();
        listItemInfo += '\nID: ' + oListItem.get_id() +  '\nTitle: ' + oListItem.get_item('Title');

        UpdateStatusLocked(oListItem.get_id(),varList);


            //ddlDepartment1.add(new Option(oListItem.get_item('Title'), oListItem.get_item('ID')));
                }

    alert(listItemInfo.toString());


}

function onQueryFailed(sender, args) {

    alert('Request failed. ' + args.get_message() + '\n' + args.get_stackTrace());
}


// -------------------------------------------------------------------------
// UPDATE LIST  ACTION
function UpdateStatusLocked(ID,varList) {

    var clientContext = new SP.ClientContext.get_current();
    var oList = clientContext.get_web().get_lists().getByTitle(varList);

    this.oListItem = oList.getItemById(ID);

    oListItem.set_item('Locked', 'True');

    oListItem.update();

    //clientContext.load(oListItem);

    clientContext.executeQueryAsync(Function.createDelegate(this, this.onQuerySucceeded4), Function.createDelegate(this, this.onQueryFailed4));

}


function onQuerySucceeded4(sender, args) {
//alert ('Updated Locked Status');

}

function onQueryFailed4(sender, args) {

    alert('Request failed. ' + args.get_message() + '\n' + args.get_stackTrace());
}

2 Answers 2

1

Promises to the rescue!

(SharePoint front-end developers -meaning, anyone writing code with JSOM- should really start to familiarize with the concept of Promises).

If you wrap your async function in a promise, you can have your loop producing a new promise, push it to an array of promises, then wait for all of them to complete and lastly, run your alert.

Take a look here at an example implementation with the Q library

1
  • Hi Promise sounds good but its another thing to learn. Is it possible to simply retun to the calling JS Function at the point of onSuccess with true or false, then depending on result the next JS function is called? May 21, 2015 at 8:54
-1

why don´t you use some variables (a set of booleans or a int with bit flags)? Each function sets ist own value to true (or another value indicating "done"). and starts a verification function. The latter one checks if all are set to true ("done") and if so, it does the alert.

This way you could do this async

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