I'd like to make a Degree object that inherits from the Number object and uses the Number constructor but adds a .rad() method that returns the value in radians.
If I do something like:
It generally works but I don't get Number's methods like toString and toPrecision.
Is there any way at all to create a new template object that inherits from the built in Date object so as to be able to add new methods to that child object without adding them to the built in Date object? I've tried everything I can think of and as far as I can tell it keeps referencing the Date function instead of the Date object and so doesn't work.
View 3 Replies View RelatedHow would I go about copying all the prototype functions AND the constructor from one object into another object, and then call them?
I know I can use this.example.call(this), but that's not an acceptable solution. I want to deploy this style over dozens, potentially hundreds of objects.
I'm hacking on a LISP interpreter in JS [1], and running into trouble with numbers and Number objects.
This is what I have:
var a = new Number(1);
var b = a;
document.writeln(a == b); // true
b = 2;
document.writeln(a == b); // false
document.writeln(a); // 1
Instead of replacing the *Number object* b with the *number* 2, I'd like to assign 2 to the value of the Number object, which should still be referenced by b *and* a. In other words, the two last lines should output "true" and "2".
Is there an internally assigned number for each JavaScript object that
I can read? If so how would I do that?
I am looking for a way to simplify a large series of �object definitions� in the form:
var Img0 ={init:function(){Img0.div = document.getElementById("img0"); Img1.init();}};
var Img1 ={init:function(){Img1.div = document.getElementById("img1"); Img2.init();}};
[Code]....
The program I have developed (for animated greeting cards) works fine but for a large number of images there are an equal number of these object definitions. I am aware of such techniques as using �+i+� in place of the numbers 0, 1, 2, ... and assigning an increasing value to i in a loop. However, I do not see a way to use such a loop here.
I need to detect the "name" of the constructor of an object. For example, myArray.constructor === Array is true, but I want something where that === 'Array' is true. I've heard of Object.constructor.name, but it's not widely compatible. (preferably without involving regular expressions)?
View 4 Replies View RelatedI am trying to understand why I had an error, or why my solution worked. In my HTML I had:
<script language="JavaScript" type="text/javascript" src="Book.js"></script>
<script language="JavaScript" type="text/javascript" src="Book_TEST.js"></script>
Book.js said:
[Code]....
Now, the code worked fine in both script. (i.e., no more error.) So far as I can tell, the only differences between the first and next version of Book.js are the comments and the whitespace. Am I missing something? Can the comments or whitespace somehow effect the logic with which this code has been executing? If I get an error like this again, is there an easier/better way to fix it than to essentially retype the code?
How to extend the constructor for the date object of the javasccript so that whenever a call is made to the constructor, I want to perform a particular action? Basically how to define wrappers for default javascript methods or objects like Date() so that I can perform some action and then invoke the original method? So basically if I have something like var a = new Date(); I want it to (say) alert the value of the date everything Date() is called and then execute the default date constructor.
View 3 Replies View RelatedI have a requirement to override the constructor of a javascript class. I have to execute the current constructor code and then call a javascript method. Basically, I need to execute a javascript method whenever an object of that particular class is created in addition to whatever is being done now. I do not want to copy and paste the current constructor code and override the initcomponent method. I am looking for an alternative for that.
View 5 Replies View RelatedI need to create a constructor for a computer object. This object must have three properties: speed, and mem_live mem_dead. Then I need to create a new object using this constructor and then have its properties displayed on the screen.Look at what I'm up to so far:
function Computer(speed, mem_live, mem_dead)
{
this.speed = speed;
[code]....
It always just shows : 4.0ghz, true, false
function show() {
var s = '' ;
for (var i = 0; i<arguments.length; s += '
'+arguments[i++]) ;
typeof(window) != 'undefined' ? window.alert(s) : WScript.Echo(s) ;
}
function f(){}
show('delete(f):',delete(f)) ; // false
g = function(){} ;
h = new g() ;
show('h:',h) ; // [object Object]
show('delete(g):',delete(g)) ; // true
show('h.constructor:',h.constructor) ; // function(){}
show('delete(h.constructor):',delete(h.constructor )) ; // true
show('h.constructor:',h.constructor) ; // function(){}
is there a delete for a object inside the constructor, while i init it?
i will try something like that:
var obj = function(a)
{
if (!a) delete this;
this.a = a;
}
Sorry, bad title. Anyway, is there a way to pass the arguments to an object
instantiated via a constructor using the arguments object and have it
expanded, so to speak, so that it doesn't appear as a single argument? I'm
sorry, this explanation is just atrocious, but I can't think of exactly how
to word it. Maybe an example...
Take for instance Function.apply. It takes 1-2 arguments, the first being
the object to use as the context, and the second being either an array or an
instance of the arguments object which are to be the arguments for the
function. I want to do something similar but I want to also basically use
the new operator so that I get back an object.
Here's a snippet of some of my code, maybe this will help:
I'm sure this question has been asked many times before, but I can't seem to get the correct terms to find the answer in Google.I understand basic JavaScript inheritance. However, everything I've read makes the inheritance work something like this:
Code JavaScript:
var ChildClass = new Function();
ChildClass.prototype = new ParentClass();
ChildClass.constructor = ChildClass;
That's fine, but what happens when ParentClass's constructor needs parameters?As an example, look at the following code:
Code JavaScript:
function Furniture(color){
this.color = color;[code)....
How could I "copy" Furniture's constructor into the Chair object? Better yet, how could I copy Furniture's constructor and then add some functionality to it?
I have a code set up something like this:
[Code]....
The problem is I keep getting an error along the lines of: TypeError: Result of expression 'house' [[object Object]] is not a constructor. It seemed to work when I wasn't passing the other objects as parameters in the constructor. I just created and assigned them later. As in:
[Code]...
I am trying to get to the bottom of javascript object, prototypes etc. I have a fairly good grasp of it, but I get confused the closer I get to the base object.prototype. FIrst of all, I was under the impression that all objects descend directly from Object. But some objects (like Array) seem to inherit properties and methods from the function.prototype. So does this mean that the chain is like this:
object -- function -- array Second, I noticed (on the mozilla javascript reference site that object.prototype inherits properties and methods from function.prototype and vice versa!? How can this be? I must be missing something important about understanding the chain?
I had read from books that the constructor property of object is inherited from its prototype. And the prototype can be changed dynamically. New property can be added to or deleted from object even it was created before the prototype change.
But I got confused on below codes.
But the actual result (both IE and firefox) is
I have static object and I want remake it to a constructor with property 'length' which would be not enumerable in for loop... This is my object and how I generate it
[Code]...
I have several classes named 'ratings_colored'. They all contain a number from 1 to 10. If the number is below 5.5, the number should become red. If not it should become green.
The code below works, but if the first .ratings_colored is higher than 5.5 it will make ALL the classes green. Even the numbers below 5.5! I tried using the 'this' but it didn't work either.
$(document).ready(function () {
I have this script that is supposed to check if a number the user guesses is the same as the randomly generated number.Problem is that the random number generated at the start of the program keeps on changing everytime I click on the "Check if I'm right" button, the random number gets generated again and I never ever get to reach the correct answer
HTML CODE
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
[code].....
Hello everyone... I've got a question about an onKeyUp event. I'm using a text box that HAS to be a negative number therefore it has to have a - sign in front of the number. Can someone point me in the right direction as to how to write a function to do this? Thanks so much...
View 5 Replies View RelatedI am working on trying to create a Picture Bingo JavaScript. I am using the standard Bingo Card Generator and it works great however, I need help coding the script so that the number are associated with a picture for example everytime number 12 would show up on the card an image would replace the number. Here is the code that I am using:
[Code]...
When updating our agency's webpage daily, [URL] I am looking for a shortcut to save time.. When I update air quality numbers. I have to put the conditions. Ex.. 50 = good 100= moderate etc etc. As you see here(bold and underlined)
[Code]...
Well instead of having to type good or moderate every-time to correlate with the numbers, I want to find a way the category can automatically default correctly when I put in just the number. Ex, if I put in the number 100, it automatically knows to issue/ put Moderate with out me having to type it. I semi wrote a code .. Yet can't seem to know how to execute. Seeing if Maybe I can get some assistance.
[Code]...
I have a function below where every time a question is submitted, it will add a new row in the table with a textbox which allows numbers entry only. My question is that I don't know how to code these features in this function:
I want the text box to be between 0 and 100, so if text box contains a number which is above 100, it will automatically change the number to the maximum number which is 100.
Does any one know how to code this in my function below in javascript:
Code:
When I used toFixed() method on a number, I thought that this method round a number to a specified approximation, but I got a surprising result, the number became string! 15.23689.toFixed(2) ==> "15.24". So does it convert the number into string?
View 6 Replies View Related