I am currently working on a project where I have the following code:
<form action='/someServerSideHandler'>
<p>You have asked for <span data-bind='text: gifts().length'> </span> gift(s)</p>
<table data-bind='visible: gifts().length > 0'>
<thead>
<tr>
<th>Gift name</th>
<th>Price</th>
<th />
</tr>
</thead>
<tbody data-bind='foreach: gifts'>
<tr>
<td><input class='required' data-bind='value: name, uniqueName: true' /></td>
<td><input class='required number' data-bind='value: price, uniqueName: true' /></td>
<td><a href='#' data-bind='click: $root.removeGift'>Delete</a></td>
</tr>
</tbody>
</table>
<button data-bind='click: addGift'>Add Gift</button>
<button data-bind='enable: gifts().length > 0' type='submit'>Submit</button>
</form>
and
var GiftModel = function(gifts) {
var self = this;
self.gifts = ko.observableArray(gifts);
self.addGift = function() {
self.gifts.push({
name: "",
price: ""
});
};
self.removeGift = function(gift) {
self.gifts.remove(gift);
};
self.save = function(form) {
alert("Could now transmit to server: " + ko.utils.stringifyJson(self.gifts));
// To actually transmit to server as a regular form post, write this: ko.utils.postJson($("form")[0], self.gifts);
};
};
var viewModel = new GiftModel([
{ name: "Tall Hat", price: "39.95"},
{ name: "Long Cloak", price: "120.00"}
]);
ko.applyBindings(viewModel);
// Activate jQuery Validation
$("form").validate({ submitHandler: viewModel.save });
I have been wondering how ko.applyBindings(viewModel); is making the binding by the name of the variable. Is Knockout searching it somehow by name? How does the template know that this is its array/data set? As a .NET developer, the concept of fetching something "by name" is not clear to me. Am I mistaken in thinking that it is fetched by name? I have read the documentation but I still do not understand how Knockout connects the template gifts() with the array named gifts from the model?
By the way, this code snippet is from the main page of Knockout.