Question

So I’m almost done with this guest list front-end application I’ve been working on. The last thing I want to do is allow a string to be passed to filter the list by name. So by subscribing to a user inputting some name into a field, I should be able to use this ko computed function for searching the array in this different way. Keep in mind that self.guests is an array of guest objects.

self.displayResults = ko.computed(function(){
    if(self.displayTypeOf() == 'slice'){
        var ary = self.guests.slice(self.startValue(),self.endValue());
        console.log(ary)
        return ary
    }else if(self.displayTypeOf() == 'string'){
        //Code I need goes here
    }
});

You can see that normally the list is computed with a sliced section of the list, when the user begins typing something in the input, I will override and update this computed list using the search array function I’m asking for.

Thanks in advance!

Answer 1

I would recommend to ko.utils.arrayFilter utility function for filtering:

self.displayResults = ko.computed(function(){
    if(self.displayTypeOf() == 'slice'){
        var ary = self.guests.slice(self.startValue(),self.endValue());
        console.log(ary)
        return ary
    }else if(self.displayTypeOf() == 'string'){
        // Init filter
        var filter = self.SomeValue();
        var ary = ko.utils.arrayFilter(self.guests(), function(item) {
           return ko.utils.stringStartsWith(item.name().toLowerCase(), filter);
        });
        console.log(ary);
        return ary;
    }
});

Read more about ko utils methods here: http://www.knockmeout.net/2011/04/utility-functions-in-knockoutjs.html