Develop Reference

Merge two custom javascript functions

This is the first function:
jQuery.fn.serializeObject = function(){
var self = this,
json = {},
push_counters = {},
patterns = {
"validate": /^[a-zA-Z][a-zA-Z0-9_]*(?:\[(?:\d*|[a-zA-Z0-9_]+)\])*$/,
"key": /[a-zA-Z0-9_]+|(?=\[\])/g,
"push": /^$/,
"fixed": /^\d+$/,
"named": /^[a-zA-Z0-9_]+$/
};
this.build = function(base, key, value){
base[key] = value;
return base;
};
this.push_counter = function(key){
if(push_counters[key] === undefined){
push_counters[key] = 0;
}
return push_counters[key]++;
};
jQuery.each(jQuery(this).serializeArray(), function(){
// skip invalid keys
if(!patterns.validate.test(this.name)){
return;
}
var k,
keys = this.name.match(patterns.key),
merge = this.value,
reverse_key = this.name;
while((k = keys.pop()) !== undefined){
// adjust reverse_key
reverse_key = reverse_key.replace(new RegExp("\\[" + k + "\\]$"), '');
// push
if(k.match(patterns.push)){
merge = self.build([], self.push_counter(reverse_key), merge);
}
// fixed
else if(k.match(patterns.fixed)){
merge = self.build([], k, merge);
}
// named
else if(k.match(patterns.named)){
merge = self.build({}, k, merge);
}
}
json = jQuery.extend(true, json, merge);
});
return json;
};
This function to serialize the form's values but the problem of this function that it's not getting the value of the unchecked inputs because that I make this function:
jQuery.fn.mySerialize = function() {
var $container = jQuery(this),
$checkboxes = $container.find("input[type='checkbox']").each(function() {
jQuery(this).val(this.checked ? 1 : 0).prop('checked', true);
});
var serialized = ($container.serializeObject());
$checkboxes.each(function() {
jQuery(this).prop('checked', jQuery(this).val() == 1);
});
return serialized;
};
And it's working as I need by directly using mySerialize function now I want to merge the edits that I make at mySerialize function to the serializeObject function because I failed to do that directly into serializeObject function because that I created the mySerialize function.
Thanks in advance and really hope anyone helps me on this.

Knockout JS setting optionsValue destroys my code

The code below is simplified, see the fiddle: http://jsfiddle.net/QTUqD/7/
Basically I'm setting the device name under the data-bind, but I also need to specify the optionsValue for sending off to the database, but when I set it, the display data-bind is blank.
<script id="extItems" type="text/html">
<tr>
<td data-bind="text: device() && device().name"></td>
</tr>
</script>
<script id="editExts" type="text/html">
<tr>
<td>
<select data-bind="options: $root.devicesForItem($data), optionsText: 'name', value: device, optionsValue: 'id'"></select>
</td>
</tr>
</script>
window.ExtListViewModel = new function () {
var self = this;
window.viewModel = self;
self.list = ko.observableArray();
self.pageSize = ko.observable(10);
self.pageIndex = ko.observable(0);
self.selectedItem = ko.observable();
self.extQty = ko.observable();
self.devices = ko.observableArray();
self.addressList = ko.observableArray(['addressList']);
self.availableDevices = ko.computed(function() {
var usedQuantities = {}; // for each device id, store the used quantity
self.list().forEach(function(item) {
var device = item.device();
if (device) {
usedQuantities[device.id] = 1 + (usedQuantities[device.id] || 0);
}
});
return self.devices().filter(function(device) {
var usedQuantity = usedQuantities[device.id] || 0;
return device.qty > usedQuantity;
});
});
// need this to add back item's selected device to its device-options,
// and to maintain original order of devices
self.devicesForItem = function(item) {
var availableDevices = self.availableDevices();
return self.devices().filter(function(device) {
return device === item.device() || availableDevices.indexOf(device) !== -1;
});
}
self.edit = function (item) {
if($('#extMngForm').valid()) {
self.selectedItem(item);
}
};
self.cancel = function () {
self.selectedItem(null);
};
self.add = function () {
if($('#extMngForm').valid()) {
var newItem = new Extension();
self.list.push(newItem);
self.selectedItem(newItem);
self.moveToPage(self.maxPageIndex());
}
};
self.remove = function (item) {
if (confirm('Are you sure you wish to delete this item?')) {
self.list.remove(item);
if (self.pageIndex() > self.maxPageIndex()) {
self.moveToPage(self.maxPageIndex());
}
}
$('.error').hide();
};
self.save = function () {
if($('#extMngForm').valid()) {
self.selectedItem(null);
};
};
self.templateToUse = function (item) {
return self.selectedItem() === item ? 'editExts' : 'extItems';
};
self.pagedList = ko.dependentObservable(function () {
var size = self.pageSize();
var start = self.pageIndex() * size;
return self.list.slice(start, start + size);
});
self.maxPageIndex = ko.dependentObservable(function () {
return Math.ceil(self.list().length / self.pageSize()) - 1;
});
self.previousPage = function () {
if (self.pageIndex() > 0) {
self.pageIndex(self.pageIndex() - 1);
}
};
self.nextPage = function () {
if (self.pageIndex() < self.maxPageIndex()) {
self.pageIndex(self.pageIndex() + 1);
}
};
self.allPages = ko.dependentObservable(function () {
var pages = [];
for (i = 0; i <= self.maxPageIndex() ; i++) {
pages.push({ pageNumber: (i + 1) });
}
return pages;
});
self.moveToPage = function (index) {
self.pageIndex(index);
};
};
ko.applyBindings(ExtListViewModel, document.getElementById('extMngForm'));
function Extension(extension, name, email, vmpin, device, macAddress, shipTo){
this.extension = ko.observable(extension);
this.name = ko.observable(name);
this.email = ko.observable(email);
this.vmpin = ko.observable(vmpin);
this.device = ko.observable(device);
this.macAddress = ko.observable(macAddress);
this.shipTo = ko.observable(shipTo);
}

When you use optionsValue, KO writes the property value to whatever you have bound against value. So, it would now populate value with the id rather than the object.
There are a couple of ways to tackle this scenario where you want both the value (for sending to the DB) and the object (for binding other parts of the UI against).
A pretty typical solution is to create a computed observable on your object that takes the currently selected object and returns the id.
So, in your Extension you would do something like:
this.device = ko.computed({
read: function() {
var device = this.device.asObject();
return device && device.id;
},
deferEvaluation: true, //deferring evaluation, as device.asObject has not been created yet
}, this);
//create this as a sub-observable, so it just disappears when we turn this into JSON and we are just left with the id to send to the DB
this.device.asObject = ko.observable(device);
Then remove the optionsValue and bind value against device.asObject
In this case, I added the asObject sub-observable, so it will just drop off when you turn this into JSON (ko.toJSON) to send to the server. The only tricky part about this technique is that if you are loading existing data from the server, then you would need to populate asObject with the appropriate choice from your options.
Here is a sample: http://jsfiddle.net/rniemeyer/Q3PEv/
Another option that I have used is to continue to use optionsValue, but then to create a custom binding that tracks the object in a separate observable. Here is a custom binding that creates an asObject sub-observable for whatever is bound against value. This way you really don't need to mess with it at all in your view model.
//when using optionsValue, still track the select object in a different observable
ko.bindingHandlers.valueAsObject = {
init: function(element, valueAccessor, allBindingsAccessor) {
var value = allBindingsAccessor().value,
prop = valueAccessor() || 'asObject';
//add an "asObject" sub-observable to the observable bound against "value"
if (ko.isObservable(value) && !value[prop]) {
value[prop] = ko.observable();
}
},
//whenever the value or options are updated, populated the "asObject" observable
update: function(element, valueAccessor, allBindingsAccessor) {
var prop = valueAccessor(),
all = allBindingsAccessor(),
options = ko.utils.unwrapObservable(all.options),
value = all.value,
key = ko.utils.unwrapObservable(value),
keyProp = all.optionsValue,
//loop through the options, find a match based on the current "value"
match = ko.utils.arrayFirst(options, function(option) {
return option[keyProp] === key;
});
//set the "asObject" observable to our match
value[prop](match);
}
};
Sample here: http://jsfiddle.net/rniemeyer/E2kvM/

How to "new" a returned function in Javascript

I am trying to simulate a namespace feature in Javascript.
var com = {};
com.domain = {};
com.domain.system = {};
com.domain.net = {};
com.domain.net.ip = {};
com.domain.net.ip.tcp = {};
com.domain.net.ip.udp = {};
com.domain.net.ip.ssl = {};
com.domain.util = {};
com.domain.util.timer = {};
com.domain.plugins = {};
com.domain.session = {};
com.domain.io = {};
com.domain.algorithm = {};
com.domain.debug = {};
This is the namespaces declaration. Later I will add functions to these namespaces.
This is my selector function:
For a convenient way to use namespaces, I add a function named $. This function will walk all namespaces in com. If the selected name exists, return the object.
function $ (selector) {
function digger (namespace, selector) {
for (var prop in namespace) {
if (typeof namespace[prop] == "array" || typeof namespace[prop] == "object") {
if (prop == selector) {
return namespace[prop];
}
var dig = digger(namespace[prop], selector);
if (dig != null) {
return dig;
}
} else {
if (prop == selector) {
return namespace[prop];
}
}
}
}
return digger (com, selector);
}
After that, I add a timer to namespace com.doamin.util.
com.domain.util.timer = function () {
this._handle = new InnerObj.SystemTimer(io);
return this;
};
com.domain.util.timer.prototype.expiresFromNow = function (seconds, cbHandler) {
this._handle.ExpiresFromNow (seconds, cbHandler);
};
com.domain.util.timer.prototype.wait = function (seconds, cbHandler) {
this._handle.Wait (seconds, cbHandler);
};
com.domain.util.timer.prototype.expiresAt = function (seconds, cbHandler) {
this._handle.Wait (seconds, cbHandler);
};
com.domain.util.timer.prototype.cancel = function () {
this._handle.Cancel ();
};
Usage:
1. var timer = new com.domain.util.timer (); OK
timer.expiresAt (1, {}); OK
2. var func = $("timer"); OK
var timer = new func (); OK
timer.expiresAt (1, {}); OK
But but but but but
var timer = new $("timer") (); NG
Can anyone tell me why the last new function is not working?

Try var timer = new ($("timer"))();.
Your question is not clear but I guess since $("timer") returns a function, you want a new instance of the result of $("timer") and not a new instance of $().

apply parameter into function within parameter array

http://jsbin.com/ukizof/1/
how do you call a function which is part of a array and set a paramater to it , as in the example below i want the script to return a function in order to call a function parameter which as below in the example is set below.
var bQuery = {
one: function(elem, options) {
options = this.extend({
method: 'html',
event: 'test2',
func:null
}, options || {});
var element = elem;
if (options.method == 'html') {
element.innerHTML = options.event;
} else if (options.method == 'append') {
element.innerHTML = element.innerHTML + options.event;
} else if (options.method == 'prepend') {
element.innerHTML = options.event + element.innerHTML;
}
return // return method to apply string to func: parameter function as below is "e"
},
extend: function(a, b) {
for (var prop in b) {
a[prop] = b[prop];
}
return a;
}
};
$ = bQuery;
$.one(document.getElementById("log"), {
method: 'append',
event: 'rjfjfjjffj',
func: function(e){
alert(e);
}
});

If I understood you right, you want
var options, element;
…
return function() {
if (typeof options.func == 'function')
return options.func(element.innerHTML);
};

Javascript: What is the preferred design for nested (inner) types?

I use Resig's makeClass() approach for constructors:
// makeClass - By John Resig (MIT Licensed)
// Allows either new User() or User() to be employed for construction.
function makeClass(){
return function(args){
if ( this instanceof arguments.callee ) {
if ( typeof this.init == "function" )
this.init.apply( this, (args && args.callee) ? args : arguments );
} else
return new arguments.callee( arguments );
};
}
// usage:
// ------
// class implementer:
// var MyType = makeClass();
// MyType.prototype.init = function(a,b,c) {/* ... */};
// ------
// class user:
// var instance = new MyType("cats", 17, "September");
// -or-
// var instance = MyType("cats", 17, "September");
//
var MyType = makeClass();
MyType.prototype.init = function(a,b,c) {
say("MyType init: hello");
};
MyType.prototype.Method1 = function() {
say("MyType.Method1: hello");
};
MyType.prototype.Subtype1 = makeClass();
MyType.prototype.Subtype1.prototype.init = function(name) {
say("MyType.Subtype1.init: (" + name + ")");
}
In that code, MyType() is a toplevel type, and MyType.Subtype1 is a nested type.
To use it, I can do:
var x = new MyType();
x.Method1();
var y = new x.Subtype1("y");
Can I get a reference to the instance of the parent type, within the init() for Subtype1() ?
How?

Nope, not unless you write a class implementation that tracks this "outer" class explicitly, Javascript won't be able to give this to you.
For example:
function Class(def) {
var rv = function(args) {
for(var key in def) {
if(typeof def[key] == "function" && typeof def[key].__isClassDefinition == "boolean")
def[key].prototype.outer = this;
this[key] = def[key];
}
if(typeof this.init == "function")
this.init.apply( this, (args && args.callee) ? args : arguments );
};
rv.prototype.outer = null;
rv.__isClassDefinition = true;
return rv;
}
var MyType = new Class({
init: function(a) {
say("MyType init: " + a);
say(this.outer);
},
Method1: function() {
say("MyType.Method1");
},
Subtype1: new Class({
init: function(b) {
say("Subtype1: " + b);
},
Method1: function() {
say("Subtype1.Method1");
this.outer.Method1();
}
})
});
var m = new MyType("test");
m.Method1();
var sub = new m.Subtype1("cheese");
sub.Method1();