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How do I set specific key for keydown event listener? [duplicate]

I am trying to use an HTML button to call a JavaScript function.
Here's the code:
<input type="button" value="Capacity Chart" onclick="CapacityChart();">
It doesn't seem to work correctly though. Is there a better way to do this?
Here is the link:http://projectpath.ideapeoplesite.com/bendel/toolscalculators.html click on the capacity tab in the bottom left section. The button should generate an alert if the values are not changed and should produce a chart if you enter values.

There are a few ways to handle events with HTML/DOM. There's no real right or wrong way but different ways are useful in different situations.
1: There's defining it in the HTML:
<input id="clickMe" type="button" value="clickme" onclick="doFunction();" />
2: There's adding it to the DOM property for the event in Javascript:
//- Using a function pointer:
document.getElementById("clickMe").onclick = doFunction;
//- Using an anonymous function:
document.getElementById("clickMe").onclick = function () { alert('hello!'); };
3: And there's attaching a function to the event handler using Javascript:
var el = document.getElementById("clickMe");
if (el.addEventListener)
el.addEventListener("click", doFunction, false);
else if (el.attachEvent)
el.attachEvent('onclick', doFunction);
Both the second and third methods allow for inline/anonymous functions and both must be declared after the element has been parsed from the document. The first method isn't valid XHTML because the onclick attribute isn't in the XHTML specification.
The 1st and 2nd methods are mutually exclusive, meaning using one (the 2nd) will override the other (the 1st). The 3rd method will allow you to attach as many functions as you like to the same event handler, even if the 1st or 2nd method has been used too.
Most likely, the problem lies somewhere in your CapacityChart() function. After visiting your link and running your script, the CapacityChart() function runs and the two popups are opened (one is closed as per the script). Where you have the following line:
CapacityWindow.document.write(s);
Try the following instead:
CapacityWindow.document.open("text/html");
CapacityWindow.document.write(s);
CapacityWindow.document.close();
EDIT
When I saw your code I thought you were writing it specifically for IE. As others have mentioned you will need to replace references to document.all with document.getElementById. However, you will still have the task of fixing the script after this so I would recommend getting it working in at least IE first as any mistakes you make changing the code to work cross browser could cause even more confusion. Once it's working in IE it will be easier to tell if it's working in other browsers whilst you're updating the code.

I would say it would be better to add the javascript in an un-obtrusive manner...
if using jQuery you could do something like:
<script>
$(document).ready(function(){
$('#MyButton').click(function(){
CapacityChart();
});
});
</script>
<input type="button" value="Capacity Chart" id="MyButton" >

Your HTML and the way you call the function from the button look correct.
The problem appears to be in the CapacityCount function. I'm getting this error in my console on Firefox 3.5: "document.all is undefined" on line 759 of bendelcorp.js.
Edit:
Looks like document.all is an IE-only thing and is a nonstandard way of accessing the DOM. If you use document.getElementById(), it should probably work. Example: document.getElementById("RUnits").value instead of document.all.Capacity.RUnits.value

This looks correct. I guess you defined your function either with a different name or in a context which isn't visible to the button. Please add some code

Just so you know, the semicolon(;) is not supposed to be there in the button when you call the function.
So it should just look like this: onclick="CapacityChart()"
then it all should work :)

One major problem you have is that you're using browser sniffing for no good reason:
if(navigator.appName == 'Netscape')
{
vesdiameter = document.forms['Volume'].elements['VesDiameter'].value;
// more stuff snipped
}
else
{
vesdiameter = eval(document.all.Volume.VesDiameter.value);
// more stuff snipped
}
I'm on Chrome, so navigator.appName won't be Netscape. Does Chrome support document.all? Maybe, but then again maybe not. And what about other browsers?
The version of the code on the Netscape branch should work on any browser right the way back to Netscape Navigator 2 from 1996, so you should probably just stick with that... except that it won't work (or isn't guaranteed to work) because you haven't specified a name attribute on the input elements, so they won't be added to the form's elements array as named elements:
<input type="text" id="VesDiameter" value="0" size="10" onKeyUp="CalcVolume();">
Either give them a name and use the elements array, or (better) use
var vesdiameter = document.getElementById("VesDiameter").value;
which will work on all modern browsers - no branching necessary. Just to be on the safe side, replace that sniffing for a browser version greater than or equal to 4 with a check for getElementById support:
if (document.getElementById) { // NB: no brackets; we're testing for existence of the method, not executing it
// do stuff...
}
You probably want to validate your input as well; something like
var vesdiameter = parseFloat(document.getElementById("VesDiameter").value);
if (isNaN(vesdiameter)) {
alert("Diameter should be numeric");
return;
}
would help.

Your code is failing on this line:
var RUnits = Math.abs(document.all.Capacity.RUnits.value);
i tried stepping though it with firebug and it fails there. that should help you figure out the problem.
you have jquery referenced. you might as well use it in all these functions. it'll clean up your code significantly.

I have an intelligent function-call-backing button code:
<br>
<p id="demo"></p><h2>Intelligent Button:</h2><i>Note: Try pressing a key after clicking.</i><br>
<button id="button" shiftKey="getElementById('button').innerHTML=('You're pressing shift, aren't you?')" onscroll="getElementById('button').innerHTML=('Don't Leave me!')" onkeydown="getElementById('button').innerHTML=('Why are you pressing keys?')" onmouseout="getElementById('button').innerHTML=('Whatever, it is gone.. maybe')" onmouseover="getElementById('button').innerHTML=('Something Is Hovering Over Me.. again')" onclick="getElementById('button').innerHTML=('I was clicked, I think')">Ahhhh</button>

onChange is not working IE8

I am dynamically creating a text area, based on the number of each user, comment for each user.
i am using the below code to do the same, it works fine in all the browser except IE8.
$(template1).find('textarea').attr({"id":'selfasgn'+aud.ASGN_ID,"onchange":'captureSelfComments('+aud.ASGN_ID+')'})
note that $(template1) is clone of one of the element in node.
template1 = reviewTemplate.clone(true);
function captureSelfComments(p_asgnid){
alert('caling captureSelfComments');
}
I tried below code, but its getting called when this element gets constructed or appened to the DOM. so i removed it.
$(template1).find('textarea').live('change',captureSelfComments(aud.ASGN_ID))
am I doing anything wrong here ?

For IE, try propertychange() as described here since IE may not always support the change event.
var lowIE = /msie (6|7|8)/gi.test(window.navigator.userAgent);
$(template1).find('textarea').live(lowIE ? 'propertychange' : 'change',captureSelfComments(aud.ASGN_ID));
Generally, it is not a good idea to do user agent sniffing but we are talking about IE... which is basically also not a good idea, generally :)

alternate option for getElementById in JS?

I have a MVC app.
I have written JS code below in the "Create" view. The code below code works perfectly in Google chrome and Mozilla Firefox; but it's not working in IE 8.
$('#PaymentType').change(function(){
var ptype=document.getElementById("PaymentType").value;
});
So I changed it to the code below and it works... on IE 8 as well
$('#PaymentType').change(function(){
var ptype = $(this).val();
});
Now, the problem is that I am not going to use getElementById anymore...
What if I want to get the values from another control? Which alternate option is there available to getElementById?

You just use $('#otherId').val() to get the value.
Also on a side note in your second code example you could've just used var ptype = this.value;

If you're using jQuery you don't need to use document.getElementById anymore.
I would be interested to know why it doesn't work though, it looks like it should.

Change background "onfocus" + other things

I have the script
<input type="text" name="name" value="Joe Bloggs" onfocus="this.value=''"/>
Just like I am doing with the onfocus="this.value…" can I change the background of the field (+ change other things?)
Also, does anyone have a better idea of how to do the script above, but so that the text reappears when the deselect it?

It's considered best practice to leave styling to CSS and logic to JS.
You can do this in css using the :focus pseudo-class. (http://www.quirksmode.org/css/focus.html) Unfortunately, it doesn't work in IE7 or lower. For those browsers, you can use javascript to add a class to the <input> to do the same thing.
CSS
input:focus, input.focus {background:#ff0}
If you are using jQuery, here is how you would do that.
$('input').focus(function(){
$(this).addClass('focus');
});
$('input').blur(function(){
$(this).removeClass('focus');
});

Something along the lines of
onfocus="this.value=''; this.style.backgroundColor='#f00'" onblur="this.style.backgroundColor='white'"
will get approximately what you want done simply, although it would also be possible for it to interact badly with presentation defined elsewhere and as such is probably rather crude to be considered a best practise.
Alternatively, you could as suggested add / remove a specific class to the element onfocus / onblur. At this point I would also second the jQuery recommendation: although it's hardly necessary just for this, you will find that it makes life with Javascript in general much more pleasant.
If you use jQuery, something like
$('input').focus(function() { $(this).addClass('focus') });
$('input').blur(function() { $(this).removeClass('focus') });
would allow you to cleanly define the appearance of focussed inputs in CSS. Consult jQuery documentation for the surrounding context necessary to make this work.

...id="name" onfocus = "javascript:yourFunction();"...
Then, your js looks something like this:
var inputFld = document.getElementById('name');<br/>
var oldval = inputFld.value;<br/>
var tempval = "";<br/>
function yourFunction(){
inputFld.value = tempval;<br/>
inputFld.className = "test" //(building from the first answer)<br/>
//do other stuff...<br/>
}
Then, you can also add an onblur="javascript:anotherFunction();" where anotherFunction() resets inputFld.value to the original value.
Note, best practices advise you should avoid those global vars and that you attach event listeners for the onblur and onfocus events rather than inlining them. But, at least, initially, you can see if this code as it is written works for you...

On your event, append the class name...
el.className+= 'test'
then set a background on that class in your css.

Adding an input field to the dom and focusing it in IE

I am trying to make a div, that when you click it turns into an input box, and focuses it. I am using prototype to achieve this. This works in both Chrome and Firefox, but not in IE. IE refuses to focus the newly added input field, even if I set a 1 second timeout.
Basically the code works like this:
var viewElement = new Element("div").update("text");
var editElement = new Element("input", {"type":"text"});
root.update(viewElement);
// pseudo shortcut for the sake of information:
viewElementOnClick = function(event) {
root.update(editElement);
editElement.focus();
}
The above example is a shortened version of the actual code, the actual code works fine except the focus bit in IE.
Are there limitations on the focus function in IE? Do I need to place the input in a form?

My guess is that IE hasn't updated the DOM yet when you make the call to focus(). Sometimes browsers will wait until a script has finished executing before updating the DOM.
I would try doing the update, then doing
setTimeout("setFocus", 0);
function setFocus()
{
editElement.focus();
}
Your other option would be to have both items present in the DOM at all times and just swap the style.display on them depending on what you need hidden/shown at a given time.

What version IE? What's your DocType set to? is it strict, standards or quirks mode? Any javascript errors appearing (check the status bar bottom left for a little yellow warning sign) ? Enable error announcing for all errors via Tools > Options > Advanced.
Oisin

The question is already answered by 17 of 26. I just want to point out, that Prototype has native mechanism for this: Function.defer()