JSFiddle - React, Tailwind, and code Playground

by Jon Kittell

HTML

<h2>Your seat reservations</h2>

<table>
    <thead><tr>
        <th>Passenger name</th><th>Meal</th><th>Surcharge</th><th></th>
    </tr></thead>
    <!-- Todo: Generate table body -->
    <tbody data-bind="foreach: seats">
        <tr>
            <td data-bind="value: name"></td>
            <td><select data-bind="options: $root.availableMeals, value: meal, optionsText: 'mealName'"></select></td>
            <td data-bind="text: formattedPrice"></td>
            <td><a href="#" data-bind="click: $root.removeSeat">Remove</a></td>
        </tr>
    </tbody>
    <button data-bind="click: addSeat">Reserve another seat</button>
</table>

JavaScript

// Class to represent a row in the seat reservations grid
function SeatReservation(name, initialMeal) {
    var self = this;
    self.name = name;
    self.meal = ko.observable(initialMeal);
    
    self.formattedPrice = ko.computed(function() {
        var price = self.meal().price;
        return price ? "$" + price.toFixed(2) : "None";
    });
}

//Overall viewmodel for this screen, along with initial state
function ReservationsViewModel() {
    var self = this;
    
    // Non-editable catalog data  would come from the server
    self.availableMeals = [
        { mealName: "Standard (sandwich)", price: 0 },
        { mealName: "Premium (lobster)", price: 34.95 },
        { mealName: "Ultimate (whole zebra)", price: 290 }
        ];
    
    // Editable data
    self.seats = ko.observableArray([
        new SeatReservation("Steve", self.availableMeals[0]),
        new SeatReservation("Bert", self.availableMeals[0])
        ]);
    
    // Operations
    self.addSeat = function() { self.seats.push(new SeatReservation("", self.availableMeals[0])); }
    self.removeSeat = function(seat) { self.seats.remove(seat); }
    self.totalSurcharge = ko.computed(function() {
        var total = 0;
        for (var i = 0; i < self.seats().length; i++)
            total += self.seats()[i].meal().price;
        return total;
    }
}

ko.applyBindings(new ReservationsViewModel());