JavaScript - Number.tofixed() Does It Convert Number Into String?

I need to check if a var (lessonnum) is a string that cannot be converted to a number, i.e. "fred" "george" "catalyst" etc. but not "5" "456" or "34564" etc.:

Code:

var lessonnum = readCookie('lesson');
if ((intro != "12")||((lessonnum != "A STRING THAT COULD BE A NUMBER"))){
do sth.
}

How could I do that?

A week or so ago Old Pedant and I discussed methods of converting string inputs to numbers. I speculated that *1 might be quicker. I have now run a test:-

Code:

<script type = "text/javascript">

var start = new Date().getTime();
for (var i =0; i <100000; i++) {
var a = "2";
a = a *1;
}
var end = new Date().getTime();
var diff1 = end - start;
alert (diff1); // 109

var start = new Date().getTime();
for (var i =0; i <100000; i++) {
var a = "2";
a = parseInt(a);
}
var end = new Date().getTime();
var diff2 = end - start;
alert (diff2); // 140

var start = new Date().getTime();
for (var i =0; i <100000; i++) {
var a = "2";
a =Number(a);
}
var end = new Date().getTime();
var diff3 = end - start;
alert (diff3); // 140


var start = new Date().getTime();
for (var i =0; i <100000; i++) {
var a = "2";
a = +a;
}
var end = new Date().getTime();
var diff4 = end - start;
alert (diff4); // 109

</script>

The results vary slightly with each run, but the conclusion is that there is no real difference between the methods - except for a = a*1 and a = +a which consistently comes in lower than parseInt() or Number(). But the differences are too small to be significant.

I am trying to figure out how to make a random number I can plug into a script count down from that number at certain times of the day until it reaches 0. I would like it to reset itself at midnight every day. I'm trying to make it work with a script I found on here that resets itself at midnight every day. So instead of it counting down too fast, it would count down to the next number after a randomly generated number of minutes until it reaches 0. But it wouldn't necessarily have to end at 0 at midnight. It could go from 845 to 323 at the end of the day at a slower pace. Is that possible?

I have a string of text, and starting from a particular spot (known to be a number), I want to find the length of that number.

Here's what I have: Code:

...

var start = [...predetermined...]
var end = 0;
while (!isNaN(sourceCode.charAt(start + end))){
   endCurrent++;
}
var myNum = sourceCode.substr(start, end) * 1;

So let's say var sourceCode = "alkdjabjasdsdf-53 dnalsdb..."; , startCurrent will already be at the "5" and I want to be able to extract the "53". What I have works, but it seems cumbersome...

Any advice?

I just noticed that my pseudo-streaming movie code causes an error with IE7.

I works fine with IE8, FireFox, Chrome... I have been looking on my own and found that it's likely a misplaced comma in my code, the other browser are debugging it, but IE7 will not. The error suggests it's where I have indicated below. I've tried removing the comma just after "about_us.jpg" and that causes the script to fail completely. Can anyone help me here, please?


Code:

<script type="text/javascript">
//<![CDATA[

flowplayer("player", {src: "http://www.mysite.org/flowplayer/flowplayer.commercial-3.2.5.swf", wmode: 'opaque'}, {
	// product key from your account
	key: '#$xxxxxxxxx',
		   // configure clip to use "lighthttpd" plugin for providing video data
    playlist: [
	{
        url: 'http://www.mysite.org/media/video/about_us.jpg',

    },   //<----error suggest here??? 
	{
        url: 'http://www.mysite.org/flowplayer/streamer.php?file=about_us.flv',
        provider: 'lighttpd',
		bufferLength: "2",
		autoBuffering: false
    }],

    // streaming plugins are configured normally under the plugins node
    plugins: {
        lighttpd: {
            url: 'http://www.mysite.org/flowplayer/flowplayer.pseudostreaming-3.2.5.swf',

			// use ${start} as a placeholder for the target keyframe
        queryString:escape('&start=${start}')
        }
    }
});
//]]>
</script>

I have an Adobe pdf fill-able form field that requires a distance computation using javascript. One of the values needed in the computation is in the format of a string as feet - inches (for example: 4'-10"). I need to convert this into a number to use to complete a computation. Does anyone have a code snippet or any ideas on how to do this. Any assistance is greatly appreciated.

Thanks.

I am delving into the coding world and while I understand the basic principle of cookies, conditional statements, arrays, etc... I am still learning how to properly implement them. Any asistance with the following situation would be greatly appreciated and help with my learning as I try to reverse engineer the logic. I have looked around the web and this forum with little success. If the situation below is too complicated, I would really appreciate even a shove in the right direction regarding the logic.

-----------------
How could I show a preset counter which counts up from a preset, beginning number toward a preset, end number? I imagine the increment and speed is set be the difference between the two numbers and a timeframe.

Assumptions:
I would rather not set the increment but edit the end number to show a steady increase. As I update that number, the increment adapts dynamically.

I would want the number/script to be useful, so it should not refresh to the beginning number on each page load (i.e. num=0). When a visitor comes to the page, it must seem like the counter has been steadily been increasing in their absence.

Coke or Pesi did something similar one time regarding cans sold to date (doubt it was plugged into a DB somewhere but rather based on a steady sales figure) and it was pretty cool.

All the best!

Say I had a bunch of elements with id names "id1", "id2". "id3" etc. Then say I had a function that adds a click handler such that when you click these elements it gets the id name with this.attributes[1].nodeValue;. Then say I had a bunch of arrays with the same names as the ids var id1 = ["data", false, 45]; var id2 = ["otherdata", true, 15]; var id3 = ["otherotherdata", null, 65];. How would I set a variable "currentid" to the array with the corresponding name as the id name? I guess the underlying question is, how would I convert a string to a variable name?

I can generate a random number between 1 and 9,
( var rand_no = Math.floor( 1 + Math.random() * 9 ); )
but I want to add that random number to a value that is enterred into an inputbox and get a total.
How can I do this using Javascript and put the result into a hidden field.
I will also need to use that same random number in another place on another form .

Thanks

Ooook so this is probably the stupidest question ever. I know in java you can take advantage of a number being an int (not double) and divide by something without getting a remainder. But in javascript you dont declare what kind of variable something is.

So my problem is: Given any double or triple digit number, how do i get all but the last digit. Like if i have 13, I need to make an int with 1. If it's 103 i need one with 10.

Thanks!!

I need to write something like this: http://justsheri.com/webscripting/wsassignment/1049950/

If you look at the code there is 52 of these <img src = './images/blank1.png'

onClick='clickCard("qh",0)'/> where clickcard("numchanges", increments by 1) how is this done?

Thanks
Danny

Hi. I'm trying to make a web page using javascript for validation, but after the last 2 functions I wrote, 2 functions don't work anymore. I attached the file so you can see for yourself. And I know there are a few things I could do to the html, but I'm saving those for last. Any idea why the scripts don't work is much appreciated. (the functions that don't work a "cont_pag1" and "cont_pag2"...btw...they worked just fine until I wrote the last few functions (the ones for the pag4 div))...And sorry for the really strange language...

Hello,

I need to be able to get a number to 2dp without rounding e.g.

14.756 needs to be 14.75

I tried .toFixed(2) but this rounds.

I thought of converting to a string and performing string functions but it seems like over kill if there is an easier way.

thanks

Hi All,

I have a problem in javascript.

When i am doing rounding of the value i am getting the o/p like 2.2e4.

I have to display this value in decimal value(2.0002) not in exponential.

Can any one please help me to resolve this issue.?

Regards,
VIjai

I need help on some code Code:

function makefarm(){
document.getElementById("farms").value ++ ; 
document.getElementById("pop").value -=2 ; 
document.getElementById("coin").value -=10 ; 
document.getElementById("lumber").value -=20 ; 
document.getElementById("CIfarm").value ++ ; 
document.getElementById("CIfarm").value ++ ; 
document.getElementById("CIfarm").value ++ ; 
document.getElementById("CIfarm").value ++ ; 
document.getElementById("CIfarm").value ++ ; 
}
function upgradefarm(){
document.getElementById("iron").value -=5 ;
document.getElementById("coin").value -=20 ; 
document.getElementById("farmupgrades").value ++ ; 
}
var food = function () {
	var f1 = document.getElementById('buttonhere');
	var f2 = '<input type="button" value="Make Farm" onclick="makefarm()" /> Farms:<input type="text" id="farms" size="1" value=0 style="background-color:transparent;border:0px solid white;" READONLY/> <input type="button" value="Upgrade Farm" onclick="upgradefarm()" /> Farm Upgrades:<input type="text" id="farmupgrades" size="1" value=0 style="background-color:transparent;border:0px solid white;" READONLY/> <br/><br/><br/> Current Income:<input type="text" id="CIfarm" size="1" value=0 style="background-color:transparent;border:0px solid white;" READONLY/>';
	f1.innerHTML = f2;
}

Code:

Coin:<input type="text" id="coin" value=50 size="1" style="background-color:transparent;border:0px solid white;" READONLY />
Lumber:<input type="text" id="lumber" value=100 size="1" style="background-color:transparent;border:0px solid white;" READONLY />
Iron:<input type="text" id="iron" value=25 size="1" style="background-color:transparent;border:0px solid white;" READONLY />
Food:<input type="text" id="food" value=100 size="1" style="background-color:transparent;border:0px solid white;" READONLY />
POP:<input type="text" id="pop" value=10 size="1" style="background-color:transparent;border:0px solid white;" READONLY />

so if i press the makefarm() button it will add to the numbers but if i press it again they will got to zero how could i make it remember the numbers?(the input boxes are the second code)