[RESOLVED] Javascript: $ Symbol Meaning
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Thread: [RESOLVED] Javascript: $ Symbol Meaning

  1. #1
    Join Date
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    [RESOLVED] Javascript: $ Symbol Meaning

    What does "$" do exactly? I've seen it in a couple of scripts.

    Ex: $name = "rocky";
    Last edited by code?; August 11th, 2008 at 03:06 AM.

  2. #2
    Join Date
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    Imperial College London, England
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    Re: Javascript: $ Symbol Meaning

    As far as I'm aware, i makes no difference, as you can start a variable name in Javascript with anything you like...

    If you've seen it in one of my scripts, it's a leftover habit because I've been doing a lot of PHP currently, and that requires that all variables begin with a $. As it (as far as I know) makes no difference, I use it to save mistakes in PHP.
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  3. #3
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    Re: Javascript: $ Symbol Meaning

    Oh ok, I just googled it and sometimes it's used for regex.

    What does
    Code:
    (div.visible(element) ? 'hide' : 'show']
    do? I want to learn about that syntax.
    Last edited by code?; August 11th, 2008 at 02:53 AM.

  4. #4
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    Re: Javascript: $ Symbol Meaning

    Quote Originally Posted by code?
    What does
    Code:
    (div.lement.visible(element) ? 'hide' : 'show']
    do? I want to learn about that syntax.
    Code:
    variable = (condition ? result1 : result2);
    Is equivalent to
    Code:
    if (condition) {
      variable = result1;
    } else {
      variable = result2;
    }
    Help from me is always guaranteed!*
    VB.NET code is made up on the spot with VS2008 Professional with .NET 3.5. Everything else is just made up on the spot.
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  5. #5
    Join Date
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    Re: Javascript: $ Symbol Meaning

    Lol, one more question...

    How would I type up a static class in javascript, So I could easily write...

    Code:
    Class.Function.DoIt();
    ...without having to write...
    Code:
    var Class = new myClass();

    Also, i googled "javascript class" and dug around and found
    Code:
    // JavaScript Pet class
    
    function Pet(name) {
        this._name = name;
    }
    
    Pet.prototype._name;
    
    Pet.prototype.getName = function() {
        return this._name;
    }
    Now, could you get _name without using the getName function?

    thats about it.
    Last edited by code?; August 11th, 2008 at 03:08 AM.

  6. #6
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    Re: Javascript: $ Symbol Meaning

    What about:
    Code:
    Pet.prototype.name;
    -OR-
    Pet.prototype.name = "NO NAME";
    As for a static class, I'll throw you a really complex example - it's a UTF-8 encoder:
    Some of the syntax is wierd - I think there using one of the JavaScript variants.
    Code:
    var Url = {
        encode : function (string) {
            return escape(this._utf8_encode(string));
        },
        decode : function (string) {
            return this._utf8_decode(unescape(string));
        },
        _utf8_encode : function (string) {
          //Code removed for sanity's sake
        },
        _utf8_decode : function (utftext) {
          //Code removed for sanity's sake
        }
    }
    
    s = Url.encode(s)
    Help from me is always guaranteed!*
    VB.NET code is made up on the spot with VS2008 Professional with .NET 3.5. Everything else is just made up on the spot.
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  7. #7
    PeejAvery's Avatar
    PeejAvery is offline Super Moderator Power Poster
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    Posts
    10,865

    Re: Javascript: $ Symbol Meaning

    The $ (dollar sign) is a custom function. It is not for regex, nor does it have anything to do with PHP.

    It was created a few years back to make the process of finding/getting elements much simpler. Take a look at this post from my website. It clarifies this well.

    Code:
    (statement) ? true : false;
    This is known as ternary logic. Nice and simple. It takes an if statement to one line and makes the processing much faster.

    Quote Originally Posted by code?
    How would I type up a static class in javascript, So I could easily write...
    Let's make this much simpler...try using objects. They go hand in hand with classes.

    Code:
    var myObject = {
      myFunction = function(str) {
        alert(str);
      },
    
      myRandomVariable: 'Hello world!'
    }
    
    // then to call it
    myObject.myFunction('Hello world!');
    Last edited by PeejAvery; August 11th, 2008 at 08:03 AM.
    If the post was helpful...Rate it! Remember to use [code] or [php] tags.

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