I was trying to understand this type of functions and how do they work, but can't find a good tutorial or page that refers to functions like this:
someName = function () {
....
....
}
Does anybody knows a good resource that explains it? I was also wondering how to call a function that is set like this.
i thought about following code snippet:
Code:
var newfunc = function() {
//...
}
[Code].....
Has anyone an idea, if my thoughts on that are correct oder if this behaviour could be a problem? And is there probably a better way to combine functions, so that all functions would be in one column?
Is it possible to make a variable available to other functions outside a function So to make it global from within a function without using a callback
function() {
var something = 'hello';
}
function(something) {
document.write(something);
}
something like that possible??
How do I make these three functions into one script?
<script type="text/javascript">
setTimeout('yourFunction();', 2500);
function yourFunction(){
document.getElementById('hide').style.display='block';
}
</script>
<script type="text/javascript">
[Code]..
This is probably more of a basic javascript question than a specificjquery function.I have this jQuery function named validateSubmit()which calls two other regular javascript functions. When using IE,both createCharts() and getDirectorIDs get called but when usingFireFox, only createCharts() gets called and never makes it togetDirectorIDs() and I'm not sure why this occurs.
<script type="text/javascript">
// make sure at least one checkbox is checked
function validateSubmit() {
[code]....
I'm trying to build a t-shirt creator application w/ php and ajax.You can see where I'm at here.Thus far, I've successfully passed the first parameter from the form via a function called from an onchange event, which uses a php script to pass simple text (for the time being, 'til i get this figured out), which you can see working on the page.trying to update the output w/ each change they make via the form. For every step, the output on the right needs to update.Should I be calling the same function for each onchange, or different functions? Here's what I'm using as far as AJAX/form goes:
Code:
function showShirt(s) {
// CHECKS IF THE STRING IS EMPTY
if (s=="") {[code]...........
I want to learn more about creating functions for element events
without having to put onclick event in every tag. For example:
<script>
document.getElementsByTagName('input').onclick = function () {
alert('hello');
}
</script>
Now, I know the above does not work as I have tried it but hopefully
the idea of what I am trying to achieve here. Basically for every input
tag, when the user triggers the event (click) it will do the same
function.
Anyway, I would more so like to learn about this type of scripting
where you assign functions to events. However, I dont know what to
search for in google and the like. Where could I learn more about this?
I have a nproblem with running commands from a loaded page;[code]Now i want to execute the alert() on page BB.html when doing the load on page AA.html.
View 2 Replies View RelatedI totally understand that in order to learn javascript I need to know how functions work, I understand the basics of passing in parameters and then calling the function with the values to maybe add something together etc I ve read countless articles about functions as well as books etc but I just dont get how they are used and when they should be used etc, the more advanced functions that have maybe 4 parameters and are doing different calculations and returning various values that get fired back into the script just totally confuses me.
What I would like to know is first of all how can I overcome this confusion and also any words of wisdom you may have. I will also add that I have no prior programming experience and have spent the last 2 months frequently hitting my head off a brick wall as I just cant understand javascript.
but i have these basic functions to show a div and all i would like to do after these run is to actually make the screen scroll to the bottom here is my code i know is wrong can you please point me in the right direction.
<script>
$(document).ready(function(){
// $("#go2").click(function(){
[code]....
Seeing the examples I have noted that you always use lambda functions. Is there any reason for that? why you don't make something like this:
I think is more clear than:
And we can edit and reuse the function easily, also if you are using an editor like Netbeans you can see all your functions in a list.
Even more, I think in some situations is faster a closure because we are not creating a new object every time we pass the function:
Is there any reason for chosing lambda functions?
I can't seem to get the syntax correct to get this to work. I'm sure it is something simple.I want to call multiple functions inside my document.ready function.The first function gets called but not the second.
$(document).ready(
function GetSuspectCollection() {
$.ajax({[code].....
I am confused about the true difference between the two below examples.
first example:
// Demonstrating a problem with closures and loops
var myArray = [“Apple”, “Car”, “Tree”, “Castle”];
var closureArray = new Array();
[code]....
Here we iterate through the length of myArray, assigning the current index of myArray to theItem variable. We declare closureArray 4 times as an anonymous function. The anonymous function in turn declares the predefined write() function, which is passed parameters. Since write() is in closureArray() a closure is created??? During each iteration, theItem is reassigned its value. The four closures reference this value. Since they reference this same value and since this value is reassigned ultimately to the value of the fourth index position, tHe time we execute closureArray later on, all four closures output the same string. This is because all four closures are within the same scope "the same environment" and therefore are referencing the same local variable, which has changed.
I have a couple of problems with this example:
1) I thought a closure is a function that is returned - the inner function is not returned above.
2) theItem is not even a local variable of the parent function (closureArray) - I thought in order for a closure to work, the inner function only accesses the local variables of the outer function, but in this case the local variable is defined OUTSIDE of the parent function.
3) the "the four closures are sharing the same environment." The thing is even in the second example, they are sharing the same environment.
Second example:
// A correct use of closures within loops
var myArray = [“Apple”, “Car”, “Tree”, “Castle”];
var closureArray = new Array();
[code]....
Here we iterate over the length of myArray (4 times), assigning the index of myArray to theItem variable. We also return a function reference to the closureArray during each iteration (closureArray[i]), where i is index number so we assign 4 functon references. So when we iterate through myArray, we immediatelly call the writeItem() fucntion passing an argument of theItem at its current value. This returns a child anonymous function and when that child function is called, it will execute a block that calls the predefined write() method. We assign that returned anonymous function to the variable closureArray. Hence, closureArray holds a reference to that anonymous function. So closureArray during each iteration holds a reference to the anonymous function and we later call closureArray, which in turn calls the anonymous function, therefore calling the predefined write() function to output the local variable of the parent function. This outputs each distinct index of myArray.
This is because since we created the closure, when we call writeItem, passing theItem argument, since theItem is a local variable of the parent function of the closure, it is never destroyed when we later call closureArray (the reference to the child anonymous function)? Yet weren't we using a closure in the first example as well? So whey wasn't those variables preserved?
I don't think it has anything to do with assigning a returned anonymous function to closureArray. Even though an anonymous function creates a new memory position in the javascript engine, therefore not overwriting the other function references we create during the iteration, it's still referring to a local variable declared outside the reference. So if it's about the closure retaining value of parent's local variable even after exiting the parent function allowing for the current indexes to be preserved, then why did the closure in the first example fail to retain each index?
I keep getting the function first as being undefined for some reason I
don't get.
I'm trying to use setTimeout() to pause execution so that an image in
my web page is switched every two seconds for another. Code:
When thebody section below iscommented out, I get hello, and when it isn't, I don't !
$("body"
).click(function
(e){
return
[Code]....
Is this a bug, is it an unavoidable aspect of the "live" architecture
I have written a number of functions designed to return frequency data on 1000 randomly chosen numbers using different math functions for the rounding. I would like to include all of these functions within the wrapper of another function so that only one call is needed to get returns from all of the 'inner' functions. However, while each of the functions works in isolation, the moment I wrap them in another function they stop working. :confused:
The following code is one of the functions 'frequencyWrapperOne' that has been wrapped in the function 'testWrapper'. A call to testWrapper does nothing.
function testWrapper()
{
function frequencyWrapperOne()
{
[Code]....
$(something).split(something),this is a function with a function as a property for that function.
View 8 Replies View RelatedI have several form in my site, that validate on onsubmit.I call all the validation functions from a file call functions.js.Here is a sample of the code that is working:
<form name="contact" action="contact-insert.php method="post" onSubmit="return checkform()">
<label class='SubHeadlbl' for='TextField1'><?php echo IDS_EFORMNAME?><br></label>
<input type='text' name='dfname' class='text_field' id='dfname1' size='70' maxlength='40'/>
</form>
all the other forms are not working. all have the same structure:
<form name="frm1000" action="frm1000-insert.php method="post" onSubmit="return checkform1000()">
<label class='SubHeadlbl' for='TextField1'><?php echo IDS_EFORMNAME?><br></label>
<input type='text' name='dfname' class='text_field' id='dfname1000' size='46' maxlength='40'/>
</form>
I don't know what is happening only one for work all the others don't.
I think my brain would have exploded otherwize. Some of the problems have been simple misspellings, but when you have been staring at the same thing for hours it can sorta slip by.Bascially Im not sure if Im using the function command properly. When Submit Details is click it should validate the form and then when Calculate is pressed calculate the form (obviously).I think maybe my var Array table is wrong? And the way the functions are set out doesnt seem it sit right.
View 10 Replies View RelatedDefine the function dollarToEuro, which consumes a number of New Zealand dollars and produces the Euro equivalent. The current exchange rate is approximately one New Zealand Dollar to fifty five Euro pence. Code the function in JavaScript. Prompt the user for an amount in New Zealand dollars and display the result.
So far i have done this coding :-
var nzd = Number(prompt("Enter The Amount Of New Zealand Dollars", "10"));
function dollarToEuro(nzdollar)
{
return (50/nzd)
}
document.write(nzd, "NZD =", dollarToEuro, "Euros");
It is not working.
How do you handle two functions? For example:
if I have two separate scripts, one that opens a popup window onclick and one that does a tool tip onmouseover, how do I tie them together inline, at the link? And i can put them in the same <script> tags in the head, right?
How do I "merge" the two functions below - checkFromDate() and
checkToDate() - so that I only have one function. I want to do the same
validation in both text fields, but only have one function that does all
the validation.
<html>
<head>
<script language="JavaScript">
function checkFromDate() {
var ToFrom = document.form.txtFromDate.value
// Do some other validation...
}
function checkToDate() {
var ToDate = document.form.txtToDate.value
// Do same validation as above...
}
</script>
</head>
<body>
Start Date : <input type="text" name="txtFromDate"
onBlur="checkFromDate()"> yyyy/mm/dd <br>
End Date : <input type="text" name="txtToDate" onBlur="checkToDate()">
yyyy/mm/dd
</body>
</html>
I am learning HTML for the first time taking a self teaching class
though my local Community College. Normally this college rocks and has
some of the best resources and down to earth teachers that pick books
that acutally help folks.
Well they failed and my book take more logic jumps that Stephen
Hawkins! :D
So my ultimate question is as follows:
How do I created a function with the following information provided:
Create a fucntion named Mquote that contains the single parameter,
Qnum.
My apologies for such little information. I am sure its my oversight
that I am unable to locate the answer to my question.
What I am looking for is the base layout for noob java functions.
I want a function to take another function as a parameter, and execute it as a line of code. I put a simplified example below, just to illustrate the idea. Does anyone know the syntax to do this, or is there perhaps a better approach entirely?
// EXAMPLE
doSomething(5, 10, functionA, functionB);
function doSomething(x, y, myFunctionA, myFunctionB) {
if (x > y) {
myFunctionA();
} else {
myFunctionB();
}
}
function functionA() {
// some code
}
function functionB() {
// some code
}
When I click on the "Check All" checkbox, it correctly checks all of the boxes in my form, but I would like each checkbox to also call hideLayer2 function just as what would occur if the user checked the boxes individually. Is there a way to call the hideLayer2 function and pass the correct whichLayer and the_box parameters within the DoToAll function? Maybe there is an easier way?
Code:
Is it possible to merge two functions like these?
<script type="text/javascript">
function showdiv(pass) {
setTimeout('showdiv2("'+pass+'")', 750);
}
function showdiv2(pass) {
var divs = document.getElementsByTagName('div');
for(i=0;i<divs.length;i++){
if(divs[i].id.match(pass)){
if (document.getElementById)
divs[i].style.visibility="visible";
}
else {
if (document.getElementById)
divs[i].style.visibility="hidden";
}}}
</script>