Question

For some reason it only removes the first row and not sure why.

function templatesArray(whatsThis) {
    var myNewArray = new Array(); 
    var aRow = new Array();

    $('input:checkbox[name="templates"]:checked').each(function(i) { 
        myNewArray.push($(this).val());
        aRow.push(oTable.fnGetPosition( $(this).parents('tr').get(0)));
    }); 
    var dataString = 'templatesArray=' + myNewArray + '&deleteTemplatesArray=True'; 
    $.ajax({ 
        type: "POST", 
        url: "processes/templates.php", 
        data: dataString,
        success: function(data) {
            if (data.errorsExist) {
            } else {
                $(whatsThis).parents("tr").eq(0).hide(); 
                for (i in aRow)  // loop over the array of row indexes
                  oTable.fnDeleteRow(aRow[i]);
                if(oTable.fnSettings().fnRecordsTotal() == 0) {
                    $('.bt_red').remove();
                    $('.bt_blue').remove();
                }
                if(oTable.fnSettings().fnRecordsTotal() <= 10) {
                    $('.bt_blue').remove();
                }
                if(oTable.fnSettings().fnRecordsTotal() <= 10) {
                    $('div.pagination').remove();
                }
            } 
        }
    });

}

Answer 1

Avoid using for .. in on Arrays. You can get unexpected results. Instead use Array.foreach or jQuery’s $.each():

$.each(aRow, function() {
    oTable.fnDeleteRow(this);
});

If that doesn’t fix it, please post more details, such as the code for oTable.fnDeleteRow(). Are any JavaScript errors being thrown?

Edit: Your code is passing the row index to the delete function. After the delete function is called all proceeding rows have a new row index. So if you try to delete rows 1, 2, and 3, you’ll end up deleting rows 1, 3, and 5. Instead store and pass a reference to the row itself:

$('input:checkbox[name="templates"]:checked').each(function(i) { 
    myNewArray.push($(this).val());
    aRow.push($(this).closest('tr')[0]);
}); 

http://jsfiddle.net/3Ldj5/2/