Question

I’m having a problem, here is the javascript/jquery

 getTextForDisplay: function() {

            var displayText = "Select...";
            var options = this.dataSource._data;

            var selectedOptions = $.filter(options, function(index){
                return this.selected;

            });

            if (selectedOptions.length == 1) {
              displayText = "length1";
            } 
            else if (selectedOptions.length > 1) {
                displayText = "Multiple...";
            } 
            return displayText;
        }
    });

so this is in regards to a multi-select dropdown box that has checkboxes, the options variable is an observable array pulling its data from a viewmodel, so what I am trying to do is to display “length1” if only one of the checkboxes is selected and to display “Multiple…” if more than one checkbox is selected, this seems pretty straightforward but I keep getting a error in when I run it. the error is c.replace is not a function and the error is in the jquery.min.js file. If I remove index from the .filter then it still doesn’t work but it doesn’t error out either.

Answer 1

jQuery doesn’t define a jQuery.filter() function (at least, not in the public API). The .filter() it does define is a method for jQuery collections.

Perhaps jQuery.grep() is what you’re looking for?

var selectedOptions = $.grep(options, function (option, index) {
    return option.selected;
});