JavaScript - Are Functions "first Class Objects?" And Javascript != Javascript

suggestions welcome !!

This is my first post.
I am reading "Javascript The Good Parts" ~ The Method Invocation Pattern Page 28

and tried this,



var myObject= {
value:0,
increment:function(inc){
this.value+= typeof inc==="number" ? inc:1;
}
}

myObject.increment(2);
alert(myObject.value);

but alert(myObject.value); is returning a value of "2", when it should return "3".

Can someone help?





Reply With Quote




12-22-2014, 09:59 AM #2
rnd me View Profile View Forum Posts Visit Homepage

Senior Coder Join Date Jun 2007 Location Urbana Posts 4,497 Thanks 11 Thanked 603 Times in 583 Posts

0+2=2, not 3; the code is working correctly.

Hi - in editing a website...this javascript html is really getting on my nerves - can somebody please tell me why i keep getting the error message

expected ")"

when i try this code: (which ive fiddled around with bloody loads to try and resolve!)

<SCRIPT LANGUAGE=JAVASCRIPT >

var r_text = new Array ();
r_text[0] = Text 0;
r_text[1] = Text 1;
r_text[2] = Text 2;

var i = Math.floor(3*Math.random());

{
document.write("<marquee style="font-family: 'Georgia'; color: #FFFF00; font-size: 13pt; mso-fareast-font-family: 'Arial'" ><scrollamount="15"><b>" + r_text[i] + "</b></scrollamount></marquee>");
}


it seems fine to me and is getting me really frustrated now

any help greatly appreciated, do whatever you like to the coding if itll work!

thankyou very much, joe.

I am pretty novice. I do not know much about the compilers or how these things run. I do however have a good eye for trends and can figure just about anything out by looking at it.

With that;

I have a game that uses a exe launcher with a built in patcher.

I have found the code for the launcher. There are several "jquery" scripts for basic components like scroll wheel. There are also things like "downloader.js", "inputs.js".

I am interested in seeing what (and more precisely how many) ip addresses are being retrieved. I fear this patcher is using a hidden bittorrent like download system.

The code for "downloader" is pretty basic. It clearly uses some other script, but I am wondering if you can point me in the direction of a utility to monitor running JS so that I can see what is being returned.

Code:

_Downloader = function()
{
	this.downloadStatusCallback = null;
}

_Downloader.prototype = 
{

	setDownloadStatusCallback: function(callback)
	{
		this.downloadStatusCallback = callback;
	},

	addDownload: function(downloadName, metaUrl, outputPath, authorizationURL) // returns bool
	{
		return document.SSNLauncher.SSNLauncher_ReturnBool('addDownload', 'string:' +  downloadName + '|' + 'string:' +  metaUrl + '|' + 'string:' +  outputPath + '|' + 'string:' +  authorizationURL + '|');
	},

	removeDownload: function(downloadName) // returns bool
	{
		return document.SSNLauncher.SSNLauncher_ReturnBool('removeDownload', 'string:' +  downloadName + '|');
	},

	getDownloadOption: function(downloadName, optionName) // returns string
	{
		return document.SSNLauncher.SSNLauncher_ReturnString('getDownloadOption', 'string:' +  downloadName + '|' + 'string:' +  optionName + '|');
	},

	setDownloadOptions: function(downloadName, enableBitSources, enableWebSources) // returns bool
	{
		return document.SSNLauncher.SSNLauncher_ReturnBool('setDownloadOptions', 'string:' +  downloadName + '|' + 'bool:' +  enableBitSources + '|' + 'bool:' +  enableWebSources + '|');
	},

	getDownloadActive: function(downloadName) // returns bool
	{
		return document.SSNLauncher.SSNLauncher_ReturnBool('getDownloadActive', 'string:' +  downloadName + '|');
	},

	setDownloadActive: function(downloadName, active) // returns bool
	{
		return document.SSNLauncher.SSNLauncher_ReturnBool('setDownloadActive', 'string:' +  downloadName + '|' + 'bool:' +  active + '|');
	}

}

function __Downloader_reportdownloadStatus(downloadName, state, active, totalBytes, bytesLeft, maxIncoming, averageIncoming, currentIncoming, maxOutgoing, averageOutgoing, currentOutgoing, bytesRead, bytesSent, scanBytesLeft)
{
	if (SSN.Downloader.downloadStatusCallback != null)
	{
		SSN.Downloader.downloadStatusCallback(downloadName, state, active, totalBytes, bytesLeft, maxIncoming, averageIncoming, currentIncoming, maxOutgoing, averageOutgoing, currentOutgoing, bytesRead, bytesSent, scanBytesLeft);
	}
}

I have tried on several occasions to teach myself programing. I can get the commands and syntax fairly easily, and I am pretty good at 'coming up' with ways to get something done. I just don't have experience in this field (I'm in medical school) so I do not know about the tools and utilities programers use and scouring the internet has been less than fruitful.

Anybody capable of pointing me in the direction of finding a utility to monitor running js (if that is even possible =/).

I use dreamweaver CS5 to explore js code.

--------------------------------------------------------------------------------

Can some1 help me at this, i am very new to javsciprt and HTML things, so as the title says, a simple bold to the selected text in a div is what i need.

below is the div area i have, so how do it??

Code:

<TD colspan="25" width="525px" style="text-overflow: ellipsis; overflow: hidden;">
<input type="hidden" $acmForms.bindText("casecomments") />
<div #if (!$acmForms.getFormAttributes().isReadOnly())
CONTENTEDITABLE 
#end 
onKeyUp="dairy_limitTextArea(this, 4000)"
onKeyDown="dairy_limitTextArea(this, 4000)" 
id="spell_casecomments" style="width:800px; height:220px; overflow: auto; border: 1px solid #bdcee5;">

</TD>

Hello ,

here is my code(which is not working on my problem) i want to remove anchor tag(href="a") will u please help....
Code:

<html>
<head><title>Welcome to DevForum</title></head>
<script language="javascript" type="text/javascript">
function Remove()
{
    var anchor = document.getElementsByTagName("a");
    var i;
    for(i=0;i<anchor.length;i++)
    {
        var anc=anchor.item(i);
        var href=anc.attributes.getNamedItem("href");
        if (href.value == "a")
        {
               anchor.item(i).attributes.getNamedItem("href").value = "";          
        }
    }
}
</script>
<body onload="Remove()">
<h1>Welcome</h1>
<a href="b">b</a>
<a href="a">a</a>

</body>
</html>

Thanks in Advance....

I am in the process of learning 'JavaScript' and I am having a problem understanding how to delete cookies. I understand that to do delete a cookie you want to set the expiration attribute of the cookie to delete, to any date in the past. My confusion lies in the exact syntax of how to do this. In the example s I have seen in books and on the internet it appears that you must submit the "exact" name/value pair that you originally set the cookie with to delete it. For an example:
var UserId = "MrJones", password = "secret";
var currentDate = new Date();
currentDate.setFullYear(currentDate.getFullYear()+1);

document.cookie = encodeURI("userid=" + UserId " + "; " +
"password=" + password + "; expires=" + currentDate.toUTCString());

What is the minimum syntax I would need to delete the cookie above?
Also, I need clarification on the terminology. Is a single cookie a collection of name/value pairs(also known as crumbs) or is each name/value pair considered a cookie unto itself?

Why does the ECMA board allow people on drugs to be part of settings standards for programming languages that will be used by the entire world?

I've been reading a book on JavaScript and have had no problems understanding anything until reaching Chapter 9 and the subject of cookies. This syntax is crazy. And the way you add to a cookie by using just an assignment operator? How about a cookie.Add() and a cookie.Delete() method?

Hi,
Please i am confuse to know the work of this sign (!)...which is exclamation sign in programming.

i have this code here which which i remove the exclamation sign (!)..it dont work but when i add it ,then it work.
Here is the code
<script type="text/javascript">
function getvalue()
{
var mytextfield=document.getElementById("mytext");
if(mytextfield.value!="")
{
alert("You Entered:"+mytextfield.value)
}
else{
alert("would you enter some text")
}
}
</script>
<input type="text" id="mytext" size="30">
<input type="button" value="check" onclick="getvalue()">

Please help me to understand the use of this sign !.

Thank you.
Clement Osei.

I am trying to add a pulldown menu with a button to my website. I have successfully done this with a javascript I found online here to give credit:
http://www.blazonry.com/javascript/js_menu.php
I tried to modify the form so it will use an image file instead of the default button. To troubleshoot I took the relevant code and put into a seperate html file. This one is using the default code from the site referenced above. This is the page published online:
http://www.keylimecomputerservice.com/test/default.html

Code:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>

<SCRIPT LANGUAGE="JavaScript"><!-- 
function openURL()
{ 

// grab index number of the selected option
selInd = document.theForm.aaa.selectedIndex; 

// get value of the selected option
goURL = document.theForm.aaa.options[selInd].value;

// redirect browser to the grabbed value (here a URL)
top.location.href = goURL; 

}

//--> 
</SCRIPT>

</head>

<body>

<TABLE SPAN="3" BORDER=1 CELLSPACING=0 CELLPADDING=0 align="center" WIDTH="60%">
	<TR>

		<TD WIDTH="33%">
		<center><font color="black">Choose a connection</font></center><br>
		<form name="theForm"> <tt>
		<center>
		<select name="aaa" size="1">
		<option selected value="#"> ---------- </option>
		<option value="/remote/connect1.exe">Connection 1</option>
		<option value="/remote/connect2.exe">Connection 2</option>
		<option value="/remote/connect3.exe">Connection 3</option>
		<option value="/remote/connect4.exe">Connection 4</option>
		<option value="/remote/connect5.exe">Connection 5</option>
		<option value="/remote/connect6.exe">Connection 6</option>
		<option value="/remote/connect7.exe">Connection 7</option>
		<option value="/remote/connect8.exe">Connection 8</option>
		</select>
		</center>
		</TD>

		<TD WIDTH="33%">
		<input type="button" value=" GO " onClick="openURL()"> </tt>
		</form>
		</TD>

		<TD WIDTH="33%">
		</TD>
	</TR>
</TABLE>

</body>

I then tried to change the form to use an image instead of the default button. Obviously I didn't do it right. THIS ONE DOES NOT WORK. When you choose a menu item and then click the image, it just refreshes the page.
Published page:
http://www.keylimecomputerservice.co.../modified.html

This is the modified code.:
Code:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>

<SCRIPT LANGUAGE="JavaScript"><!-- 
function openURL()
{ 

// grab index number of the selected option
selInd = document.theForm.aaa.selectedIndex; 

// get value of the selected option
goURL = document.theForm.aaa.options[selInd].value;

// redirect browser to the grabbed value (here a URL)
top.location.href = goURL; 

}

//--> 
</SCRIPT>

</head>

<body>

<TABLE SPAN="3" BORDER=1 CELLSPACING=0 CELLPADDING=0 align="center">
	<TR>

		<TD WIDTH="33%">
		<center><font color="black">Choose a connection</font></center><br>
		<form name="theForm"> <tt>
		<center>
		<select name="aaa" size="1">
		<option selected value="#"> ---------- </option>
		<option value="/remote/connect1.exe">Connection 1</option>
		<option value="/remote/connect2.exe">Connection 2</option>
		<option value="/remote/connect3.exe">Connection 3</option>
		<option value="/remote/connect4.exe">Connection 4</option>
		<option value="/remote/connect5.exe">Connection 5</option>
		<option value="/remote/connect6.exe">Connection 6</option>
		<option value="/remote/connect7.exe">Connection 7</option>
		<option value="/remote/connect8.exe">Connection 8</option>
		</select>
		</center>
		</TD>

		<TD WIDTH="33%">
		<input type="image" src="connectbutton.jpg" onClick="openURL()"> </tt>
		</form>
		</TD>

		<TD WIDTH="33%">
		</TD>
	</TR>
</TABLE>

</body>

Any and all help is appreciated.

Runout74

Hi

I have developed an internet mapping site which uses an html viewer with various frames to pull in a mapping window, a legend / key and a frame of tools amongst other things.

It works absolutely fine in Internet Explorer version 6, but whilst testing it in Internet Explorer 7, my mapping window is not loading up the image.

It might seem strange me posting this in a javascript forum but as the error is javascript related I thought I would give it a shot!

The error message I am receiving is "Access is denied".

After looking online, it appears as though this error could be linked to the use of frames; and those frames trying to access other windows with different document domains?? Does anyone know if new security measures have been implemented in IE7 which restricts the use of frames?

My code is below; does anyone notice anything that might give this kind of javascript error?

Any help will be greatly appreciated as I do not tend to dable too much in javascript!

Code:

<META HTTP-EQUIV="Pragma" CONTENT="no-cache">
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<TITLE>Intranet GIS Service</TITLE>
<HTML>
<HEAD>
	<SCRIPT LANGUAGE="JavaScript" SRC="javascript/aimsResource.js" TYPE="text/javascript"></SCRIPT>
	<SCRIPT TYPE="text/javascript" LANGUAGE="JavaScript">	
		
		// Designer will set the next variable - theTitle
		//var theTitle = "Intranet GIS";
		var theTitle = "";
		if (theTitle.indexOf("###TITLE##")!=-1) theTitle = titleList[0];
		var cmdString = document.location.search;

		var webParams = cmdString;
		var reloadTimer=0;
		document.writeln("<TITLE>" + theTitle + "</TITLE>");
		
		function doIt() 
		{
			MapFrame.useJava=false;
			MapFrame.checkParams();
		}
		function replacePlus(inText) 
		{
		     var re = /\+/g;
		      inText = inText.replace(re," ");
		     return inText;
		}
		
		function reloadApp() 
		{
			//window.clearTimeout(reloadTimer);
			//reloadTimer = window.setTimeout("document.location.href = 'viewer.jsp' + cmdString",1000);
			
			//Above code replaced with this. Only the map should refresh after a resize, otherwise
			//all added datashare layers are lost.

			MapFrame.mWidth = MapFrame.getMapWidth();
			MapFrame.mHeight = MapFrame.getMapHeight();
			MapFrame.sWidth = screen.width;
			MapFrame.sHeight = screen.height;
			MapFrame.loadBannerLeft = parseInt((MapFrame.mWidth - 119)/2);
			MapFrame.loadBannerTop = parseInt((MapFrame.mHeight - 72)/2);
			MapFrame.document.getElementById("theMap").style.width = MapFrame.sWidth;
			MapFrame.document.getElementById("theMap").style.height = MapFrame.sWidth;
			
			MapFrame.iWidth = MapFrame.mWidth;
			MapFrame.iHeight = MapFrame.mHeight;
			
			MapFrame.legHeight = MapFrame.iHeight - 160;
						
			var cmd = 'MapFrame.sendMapXML();';
			cmd += 'MapFrame.document.getElementById("theImage").style.width = MapFrame.mWidth;';
			cmd += 'MapFrame.document.getElementById("theImage").style.height = MapFrame.mHeight;';
			
			window.clearTimeout(reloadTimer);
			reloadTimer = window.setTimeout(cmd,1000);
		}	
	
	</SCRIPT>
</HEAD>

<SCRIPT LANGUAGE="JavaScript" TYPE="text/javascript">
	var browser = navigator.appName;
	var moreStuff = 'onresize="reloadApp()"';
	var addNS = 0;
	if (browser=="Netscape") 
	{
		addNS = 3;
	}
	document.writeln('<FRAMESET ROWS="' + (45+addNS) + ',*,30,0" FRAMEBORDER="No" FRAMESPACING="0" onload="doIt()" BORDER=2 ' + moreStuff + '>');
	document.writeln('<FRAME NAME="TopFrame" SRC="topbar.htm" MARGINWIDTH="5" MARGINHEIGHT="0" SCROLLING="No" FRAMEBORDER="No" NORESIZE>');
	document.writeln('<FRAMESET COLS="' + (30+addNS) + ',*,270" FRAMEBORDER="No" FRAMESPACING="0" BORDER="2">');
	
</SCRIPT>
		<FRAME NAME="TextFrame" SRC="text.htm" MARGINWIDTH="0" MARGINHEIGHT="0" SCROLLING="No" FRAMEBORDER="No" NORESIZE FRAMESPACING="0" BORDER="2">
		
		<!-- If textframe is used-->
		<FRAMESET ROWS="*,115">	
			<FRAME NAME="MapFrame" SRC="MapFrame.htm" MARGINWIDTH="0" MARGINHEIGHT="0" SCROLLING="No" FRAMEBORDER="Yes" RESIZE="YES">
			<FRAME NAME="ToolFrame" SRC="blank.htm" MARGINWIDTH="0" MARGINHEIGHT="0" SCROLLING="Auto" FRAMEBORDER="No" RESIZE="YES">
		</FRAMESET> 
		 
		<!-- If textframe is not used -->
		<!--<FRAME NAME="MapFrame" SRC="MapFrame.htm" MARGINWIDTH="0" MARGINHEIGHT="0" SCROLLING="No" FRAMEBORDER="No" RESIZE="YES">-->
		
		<FRAME NAME="TOCFrame" SRC="TOCFrame.htm" MARGINWIDTH="0" MARGINHEIGHT="0" SCROLLING="Auto" FRAMEBORDER="No" RESIZE="YES">
	</FRAMESET>
	<FRAMESET COLS="400,*" FRAMEBORDER="Yes" BORDER=2 FRAMESPACING="0">
		<FRAME NAME="ModeFrame" SRC="bottom.htm" MARGINWIDTH="0" MARGINHEIGHT="0" SCROLLING="No" FRAMEBORDER="No" NORESIZE>
		<FRAME NAME="ModeFrame" SRC="bottom.htm" MARGINWIDTH="0" MARGINHEIGHT="0" SCROLLING="No" FRAMEBORDER="No" NORESIZE>
	</FRAMESET>
	<FRAME NAME="PostFrame" SRC="jsForm.htm" MARGINWIDTH="0" MARGINHEIGHT="0" SCROLLING="No" FRAMEBORDER="No" NORESIZE FRAMESPACING="0" BORDER="2">
</FRAMESET>

<NOFRAMES>
<BODY>
<P>
</BODY>
</NOFRAMES>
</HTML>

Code:

<script type="text/javascript">
function loadText()
{
var t1=setTimeout("document.getElementById('data').innerHTML='<center><img style=\"margin-top:30px;\" src=\"loading.gif\"  /></center>'",0000);
var t2=setTimeout("document.getElementById('data').innerHTML='THEPAGE'",6000)
}
</script>

The above is in the header, and I'm calling it in the html.

Code:

<script type="text/javascript">
document.write(loadText());
</script>

in the page it displays properly, but then it also says "undefined" not sure why? anyone have any ideas?

Hey everyone,

Below is the code for a javascript timer. I don't understand why the way I'm using the windows object setInterval isn't working. I've highlighted the problematic areas. Please have a look.

Code:

function timer() {
	
	var display = document.getElementById('countdown'); //creates the dom by getting span with id of "countdown".
	var time = new Date(60*10*1000);
	
	function zeroPad(number) { //places a 0 in front of the number if it's less than 10. For example 09 or 08. 
		if (number<10)
			return '0' + number;
		else 
			return number;
			};
		
	function interval() {
		
		var min = zeroPad(time.getMinutes());
		var sec = zeroPad(time.getSeconds());
		display.innerHTML =  min + ":" + sec ; //Displays the time in the span with the id of "countdown".
		time.setSeconds(time.getSeconds()-1);
		
		if (time < 0) {
			alert("Times UP");
                        break;

			}
		};
		 window.setInterval(interval(), 1000);  //Why isn't the setInterval working once the timer is initiated?!!! 
}

window.onload = timer; //initiates the function

I don't understand why the setInterval isn't working. It should be calling the function every second- what's wrong with the code? Thanks!

Hi, I'm having some issues turning this "Please Wait"/Disabled button into a function.

Code:

<input type="submit" value="Submit Form" onClick="this.disabled = 'true'; this.value='Please wait...';" />

Code:

function pleasewait()
{
this.disabled = 'true';
this.value='Please wait..'
}

<input type="submit" value="Submit Form" onClick="pleasewait();" />

Thanks much

Hi all,
I have an <img> place holder in my HTML, and when users 'onclick' different button's, a javascript function is called that makes different images appear within the <img> place holder. ie. the src changes. See below:

Code:

<body>
<img id="image_space" src="" />

<button type="button" onclick="imageChange(/image1.jpg)">Image 1</button>
<button type="button" onclick="imageChange(/image2.jpg)">Image 2</button>

<script>
function imageChange(image){
document.getElementById("image_space").src=image;
}
</script>
</body>

Strait forward enough. I also have a third button, which activates a different javascript function to display an image within a different <img> place holder. BUT, I only want this button to work IF "/image2.jpg" is the ACTIVE image within the original <img> place holder (with id="image_space").
How can I write some javascript code that will identify that image as being ACTIVE? The final code with the missing "link" is described below:

[CODE]
Code:

<body>
<img id="image_space" src="" />
<img id="image_space2" src="" />

<button type="button" onclick="imageChange(/image1.jpg)">Image 1</button>
<button type="button" onclick="imageChange(/image2.jpg)">Image 2</button>
<button type="button" onclick="thirdImageChange(/image3.jpg)">Image 3</button>

<script>
function imageChange(image){
document.getElementById("image_space").src=image;
}

function thirdImageChange(thirdImage){
if (missing code here that says "/image2.jpg ACTIVE in <img id="image_space">)
{
document.getElementById("image_space2").src=thirdImage;
}
}
</script>
</body>

Sorry it's so long winded! I hope I made it clear enough. Your help would be GREATLY appreciated. Thanks for reading!