Sortable Table

by zakkarygrahamm

HTML

<table>
<thead>
    <tr data-bind="foreach: headers">
        <th data-bind="click: $parent.sort, text: title"></th>
    </tr>
</thead>
    <tbody data-bind="foreach: people">
        <tr>
            <td data-bind="text: firstName"></td>
            <td data-bind="text: lastName"></td>
            <td data-bind="text: age"></td>
        </tr>
    </tbody>
</table>

CSS

th
{
    cursor:pointer;
}

JavaScript

var viewModel = function(){
    var self = this;
    self.people = ko.observableArray([
        {firstName:'James',lastName:'Smith',age:38},
        {firstName:'Susan',lastName:'Smith',age:36},
        {firstName:'Jeremy',lastName:'Smith',age:10},
        {firstName:'Megan',lastName:'Smith',age:7},
        {firstName:'James',lastName:'Jones',age:40},
        {firstName:'Martha',lastName:'Jones',age:36},
        {firstName:'Peggy',lastName:'Jones',age:10}
    ]);
    self.headers = [
        {title:'First Name',sortPropertyName:'firstName', asc: true},
        {title:'Last Name',sortPropertyName:'lastName', asc: true},
        {title:'Age',sortPropertyName:'age', asc: true}
    ];
    self.activeSort = self.headers[0]; //set the default sort
    self.sort = function(header, event){
        //if this header was just clicked a second time
        if(self.activeSort === header) {
            header.asc = !header.asc; //toggle the direction of the sort
        } else {
            self.activeSort = header; //first click, remember it
        }
        var prop = self.activeSort.sortPropertyName;
        var ascSort = function(a,b){ return a[prop] < b[prop] ? -1 : a[prop] > b[prop] ? 1 : a[prop] == b[prop] ? 0 : 0; };
        var descSort = function(a,b){ return a[prop] > b[prop] ? -1 : a[prop] < b[prop] ? 1 : a[prop] == b[prop] ? 0 : 0; };
        var sortFunc = self.activeSort.asc ? ascSort : descSort;
        self.people.sort(sortFunc);
    };
}

ko.applyBindings(new viewModel());