Question

I created a recursive loop to delete items in a SharePoint list with SPServices. I put a timeout in for 5 seconds; however for some reason it only deletes 2 items at a time, and then executes the wait instead of deleting the batch, and then repeating the function.

Please find my code below:

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.5/jquery.min.js"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/jquery.SPServices/0.7.1a/jquery.SPServices-0.7.1a.min.js"></script>
<script type="text/javascript">

    $(document).ready(function () {
        $intStart = 1;
        $intCount = 10;
        $intEnd = 40;

        $("input[class='buttonpush']").click(function () {
            var looper = function () {
                if ($intStart < $intCount && $intStart < $intEnd) {
                    $().SPServices.SPUpdateMultipleListItems({
                        webURL: "http://widgettest",
                        listName: "TestList",
                        CAMLQuery: "<Query><Where><And><Gt><FieldRef Name='ID' /><Value Type='Counter'>" + $intStart + "</Value></Gt><Lt><FieldRef Name='ID' /><Value Type='Counter'>" + $intCount + "</Value></Lt></And></Where></Query>",
                        batchCmd: "Delete",
                        valuepairs: [],
                        debug: false,
                        completefunc: function (xData, Status) {
                            $intStart = $intStart + 5;
                            $intCount = $intCount + 5
                            setTimeout(looper, 5000);
                        }
                    });
                }
                else { 
                }
            }
            looper();
        });
    });

</script>

Answer 1

OK, now that you show the initial call to looper(), there does not appear to be anything wrong with the logic. looper() should run 8 times until $intStart is equal to 41. These are the reasons that you might not get as many successive runs of looper() as you are expecting:

1. You get an error from $().SPServices.SPUpdateMultipleListItems() and completeFunc is not executed like you are expecting.
2. Something else in your code is manipulating the values of the global variables $intStart, $intCount or $intEnd so they get changed accidentally while you are running and thus the loop doesn’t run as many iterations as expected.
3. You get a javascript exception somewhere during the running of looper() that causes execution to stop.

To debug this, just put a unique console.log() statement right before the call to $().SPServices.SPUpdateMultipleListItems() and another one in the completeFunc so you can tell exactly how far it’s getting before stopping.

Some other observations on the code:

1. $intStart is always less than $intCount since it starts less and both are incremented by 5 so you don’t need that part of the if statement.
2. It is not customary to preceded javascript variables with a $ sign unless you are connoting some special kind of variable. That is not the case here and just impedes the readability of the javascript to someone familiar with javascript.
3. Your variables $intStart, $intCount or $intEnd should probably not be global variables and in all cases should not be implicitly declared or accidentally declared globals. If you mean for them to be globals, then declare them as globals in the global scope using var. If you mean for them to be local to some scope, then declare them in that scope.
4. Because your variables are global and are only initialized one at document.ready() time, your button push will only work the first time. It will never do anything when pushed a second time.
5. Your code is not protected from the user pushing the button again while looper() is running (this will cause duplicate requests to be launched).

Here’s what your CAMLQuery will be the first two times:

<Query>
    <Where>
        <And>
            <Gt>
                <FieldRef Name='ID' />
                <Value Type='Counter'>1</Value>
            </Gt>
            <Lt>
                <FieldRef Name='ID' />
                <Value Type='Counter'>10</Value>
            </Lt>
        </And>
    </Where>
</Query>"    

<Query>
    <Where>
        <And>
            <Gt>
                <FieldRef Name='ID' />
                <Value Type='Counter'>6</Value>
            </Gt>
            <Lt>
                <FieldRef Name='ID' />
                <Value Type='Counter'>15</Value>
            </Lt>
        </And>
    </Where>
</Query>"    

This doesn’t look correct to me. The first time, you’re asking to process > 1 && < 10. The second time, you’re asking to process > 6 && < 15.

Shouldn’t the second time be > 9 && < 18 to get new ones that weren’t already processed?