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JavaScript - What Are The Differences?
What are the differences between these?
1. Code: document.domain 2. Code: window.location.hostname 3. Code: self.document.location.hostname #1 and #2 I would think are very cloes, #3 would be if someone framed the site the script was on, it would show the framed site, and not the site that is framing? because of self. Similar TutorialsCan someone explain to me the differences between the following code snippets? Mainly i don't understand the purpose of using prototype and not sure if there is a functional difference between the syntax of declaring functions. Code: var myObj = function () {
this._myInt = 1;
}
myObj.prototype = {
myNewFunction: function() {
this._myInt = 2;
}
}
VERSUS Code: var myObj = function () {
this._myInt = 1;
function myNewFunction(){
this._myInt = 2;
}
}
Hi all, This is my first post of many and am new to JS. I'm familiar with Java so I shouldn't be too lost. What I'm about to do is add support for a web app from Firefox to IE that uses OpenLayers. I've searched and found a link to this site from another thread which had a list of supported functions and what not he http://www.quirksmode.org/dom/w3c_core.html From what I've read in the last hour it seems as though I will have to use some browser sniffing (isMozilla, isIE8, etc) and have multiple conditions (if-else's) in my functions to use the proper calls. Does anyone have extra material that contains differences between IE and firefox? Someone mentioned to me that in lists IE doesn't support trailing commas but ff does.. Things like this would be very helpful Thanks, Chris Hi, I wrote some javascript for a slideshow. The main webpage contains: Code: <FORM NAME="myform"> <IMG SRC="firstimage.jpg" NAME="mypic"><br> <INPUT TYPE="text" SIZE="180" NAME="mycaption" VALUE="First Caption"> <INPUT TYPE="button" VALUE="Prev" NAME="prevbutton" DISABLED=true ONCLICK="slideshowBack()"> <INPUT TYPE="button" VALUE="Next" NAME="nextbutton" ONCLICK="slideshowUp()"> </FORM> which assigns the image and caption for the first picture, and sets the Prev and Next buttons to disabled and not disabled respectively. So you start with the first image and caption, and an enabled "Next" button. I have global javascript variables: num (init to 1), max (init to 7), img1..7 (new Image ()), img1..7.src (filenames for the images), text1..7 (captions for the images), map1..7 (maps for the images). The function for moving to the next slide is: Code: function slideshowUp()
{
num=num+1
if (num==max+1)
{num=1}
document.mypic.src=eval("img"+num+".src")
document.getElementById("mypic").useMap=eval("map"+num)
document.myform.mycaption.value=eval("text"+num)
document.getElementById("prevbutton").disabled=(num==1)
document.getElementById("nextbutton").disabled=(num==max)
}
I developed this in HMTLPad (10.2) and it works perfectly in that program's preview mode. But it won't work in the main browsers! In IE 9 (9.0.33), when you click the Next button, nothing at all happens. Image and caption stay the same, Next stays enabled, Prev stays disabled. Maps don't work. Chrome (38.0.2125.122 m) and Firefox (27.0) behave like each other. The images change, but not the captions or the Prev/Next buttons. Maps don't work. Is this to be expected? If so, how do I work around it? I'm trying to find the difference between 2 times. Time formats are 00:00:00.0 For example... var t1 = "00:07:51.0"; var t2 = "00:53:21.0"; How do I calculate the difference between those 2 times? TIA. I'm sure this is old news, but I am trying to use the CSS Horizonal List Menu script on JavascriptKit and having some display problems. http://www.javascriptkit.com/script/...stopmenu.shtml It works well except that I can't seem to get the CSS settings to display the same way in FF and IE. I can use pixel settings for the box size to get the menu across the entire screen in FF, but it only goes about 80% of the way in IE. If I maximize for IE, then the FF menu wraps. The % options for box size don't seem to work either. I am using Dreamweaver 4 for css settings. Is this just a limitation in the way the two browsers interpret the code? If there is an easy fix I could try it, otherwise I can live with what I have. I just need to know if there is some way to deal with it or not. If interested, the current version is at: www.chromafrica.com/template/template2.html. Greeting Everyone, Can anyone breakdown the differences between programming languages in VERY VERY BASIC plain English? (i.e. HTML use for website format, CSS used for the graphics on the webpage) Here's what I have questions about: 1. Differences between the most commonly used programming languages for software/web development (Javascript, Ruby on Rails, Phyton, etc.). 2. How do you determine which programming languages to use? 3. What factors are considered? Thank in advance for the people that reply. =) The following code results in the exact same output. Is there an advantage to using i++ over ++i (or visa-versa) in the loop? Code: <script type="text/javascript">
var tarr1 = []; for (var i=0; i<10; i++) { tarr1.push(i); }
var tarr2 = []; for (var i=0; i<10; ++i) { tarr2.push(i); }
alert(tarr1.join(',')+'\n'+tarr2.join(','));
</script>
Similar question for the increment method in the following: Code: <script type="text/javascript">
var tarr1 = []; var i=0; do { tarr1.push(i); i++; } while (i<10);
var tarr2 = []; var j=0; do { tarr2.push(j); ++j; } while (j<10);
alert(tarr1.join(',')+'\n'+tarr2.join(','));
</script>
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. Hello, As a novice, I'm not sure which one to use though. I'm trying to do a calculation with numbers in JavaScript using variables, particularly adding variables. Any guided understanding of this concept is welcome. For example: Code: n = parseint(n) document.write(n += m) |
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