I have been struggling with a form wizard all day. I'm using jquery stepy (form wizard) along with validation plugin. To cut a long story short, my first step is to get MySQL connection from form controls details. On submit ('next' button) a check is made on an empty hidden control ('hid').
So, if the function checkDBData passes, false should be returned, so that the form can progress to the next step. If the connection details fail, true is returned so that an error msg is posted.
Here's the checkDBData function:
function checkDBData(){
var host = $('#mysql_host').val();
var username = $('#username').val();
var password = $('#password').val();
var dbname = $('#dbname').val();
The return values don't find their way back to the rules. However, if I hard code false and true to the function...
function checkDBData(){
var host = $('#mysql_host').val();
var username = $('#username').val();
var password = $('#password').val();
var dbname = $('#dbname').val();
$.post("install/sqlcheck.php",
{"host": host,"username": username, "password": password, "dbname": dbname},
function(msg){
if(msg.required == false){
return false;
}else{
return true;
}},
"json"
);
return false; //or return true for testing purposes
}
This works. I assume it's due to the asynchronous nature of the ajax call.
i've got a function which makes a call to the database( via jquery $.post) to check if a username already exists. All the data I get back is fine and both the conditional statment works as intentded. I just can't get the function to return a value to the other function that calls it. Could this be something to do with the scope.
I have a problem with understanding jQuery. In my case I have this JS file with following content (see below). This is an anonymous function, isn't it? The problem is this line:
I have the code this way in order to consolidate it since I would prefer to do that instead of checking the selected ID and manually checking against all possible IDs (which works flawlessly, it just takes up about 5x the lines and is not modular). What I have above also works, but there is one fatal flaw:
It seems like the anonymous function that is the onclick for each unselected element becomes "return changeTo(tab + '_id')", but I don't want it to be that. I want the argument to actually be what tab is instead of the variable.
What ends up happening is that after changeTo() is called for the first time, any element you click will result in the last element being the selected one, as if it's using the final value of tab as its return value.
This doesn't make any sense, though, since tab is local, and deleting it before the function exists doesn't work. Deleting elem at the end of the for loop doesn't work. I honestly don't understand what's going on or why it doesn't set the new onclick value correctly.
Basically I just want changeTo(tab + '_id'); to turn into changeTo('MYID_id'); instead, but it simply doesn't do that and I can't figure out a way how.
I have several functions with code along the lines of:
var xmlDoc = requestXML("ajax.asp?SP=SelectRelatedTags&tag=" + array[i]);
The requestXML() function includes the code:
var xmlDoc = null; http_request.onreadystatechange = function() { if (http_request.readyState == 4) { if (http_request.status == 200) { xmlDoc = http_request.responseXML; } else { alert('There was a problem with the request.' + http_request.status); }}}; http_request.open('GET', url, true); http_request.send(null); return xmlDoc;
However, the last line (the return) executes before the readyState reaches 4. How do I return the xmlDoc to the functions only once the xmlDoc has been assigned? I tried putting the return statement in a while loop with the condition that the readyState must = 4 - this worked, but makes the browser popup a message saying the script is slowing down the system.
I did search the forums but couldn't seem to find anything on this specifically. I basically need to pass a key event and a 'name' to nameCheck() after 3 seconds. This works fine in Firefox but Internet Explorer gives the error: Member not found. I'm more of a PHP guy than a JS one
<input type="text" onkeyup="nameCheckTimer(this.value, event)" value="" /> function nameCheckTimer(name, evt) { setTimeout(function(){return nameCheck(name,evt)}, 3000); } function nameCheck(name, evt) { //need name and the key event to be available here. I have code to handle the key codes which works fine }
I'm working with nested functions and trying to pass a 'this' value to an anonymous being used in an assignment for an event listener.So, this should plop a button inside our DIV and when clicked I'd like it to run the alert-ding; unfortunately it seems to want to run the function as defined under the buttons object which doesn't work out too well.
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 am trying to create an anonymous function for onchange event of file field, so that when a file is selected, the covering text field gets that value. I know how to accomplish this by adding onchange="", but I'd prefer not do that. The code that I have almost works, except that the function in the for loop can't call on the "i" variable that the loop uses.
for( i = 0; i < source.length; i++) { source[i].onchange = function() { name[i].value = this.value; } }
So I'm currently working on a ASP.NET Webforms site and I've run in to a small problem. On my .cs file I have the following Webmethod
[WebMethod] public static string IsJobEditable(int jobid){ try{ string isEditable = "false"; JobsBLL jbl = new JobsBLL(); int jobStatusId = jbl.GetJobStatusId(jobid); //If the jobs is either waiting or being edited it is okay to edit it if(jobStatusId == Convert.ToInt32(ConstantsUtil.JobStatus.Waiting) || jobStatusId == Convert.ToInt32(ConstantsUtil.JobStatus.Edit)){ isEditable = "true"; }return isEditable; }catch (Exception ex){ throw ex; }}
This function in this case will ALWAYS return TRUE as a string. On Aspx page I have the following $(function () { $.ajax({ type: "POST", url: "Coordination.aspx/IsJobEditable", data: "{jobid:" + jobid + "}", contentType: "application/json; charset=utf-8", dataType: "text", success: function (result) { alert(result);
//This is written out in the alert {"d":"true"} I want this in a variable as a string so I can do a check on it before I do some other actions. The format is not a String so I cannot split on it to retrieve the "true" part. }, error: function (err, result) { alert(err); } });});
As you can see in the comments the value I get back in the Callback method is in to me a weird format. The type is unknown and I need this value to be able to proceed with my entire method surrounding the small portion of the Javascript. Where to access the result variable / data as a var or anything else that will let me put it into a var (as a string).
So I create a class: function cMap(mapID){//vars and stuff}
I go and prototype a function: cMap.prototype.loadMap = function(){ //jquery AJAX call }
Now in the jquery $.ajax({...}); call, I use an anonymous function on the "success:" call: success: function(data){ this.member = data; }
My problem is that inside this anonymous function call I'm trying to call a class member of my cMap class to store the data in from the AJAX call, but it's out of scope. So the JS console in FF/Chrome throws errors about bad value/doesn't exist.
How can I access this class member from inside an anonymous function? Or at least what's a good way to go about doing all this?
I am writing a small data entry screen that will post the form data to a page and return a message. But i cannot get the Success or Error functions working properly.
Here's the code where strData is the posted querystring of:
I'm not sure whether it should be in a form and using the onsubmit or click of a button.
I'm trying to "progressively enhance" one of my surveys using javascript. Basically, I have rating scales that make use of radio buttons as each point on the scale. Each radio button occupies its own cell in a table. I wrote some functions that will highlight cells on mouseover in a color corresponding to its position on the scale (e.g. the lowest point is red, the midpoint is yellow, the highest point is green). When a radio button is clicked, the background of the button's cell and preceding cells in the same row will be colored accordingly. The functions are working well in FireFox and Chrome (I just have to add a few lines using the addEvent function to make it compatible with IE).
The effect looks a lot nicer when I add a function that makes the visibility of the radio buttons hidden.
However, I want to make sure that there is a fallback option in case the functions that color the cells don't work for whatever reason. I would not want the radio buttons hidden in this case.
Is there a method whereby I can call the "hideRadiobuttons" function only if the other functions are successfully executed?
Afternoon all, Have a pretty simple function, that requests a number to be entered. I want to return that number, but i seem to be typing something wrong in the return value.
function newFunction(a, b) { var newArray = new Array(a); for (var i = 0; i < 5; i = i + 1)
I am populating a field on my page using a php include. I am asking javascript to update another element with that field's value. The value written to the select input box is Ƈ:Any Provider'. The process works fine in Firefox. In IE6 it does not write. the value nor does it throw an error. What am I doing wrong?
function postthis(){ var provider = document.inputForm['provider'].value; var report = document.getElementById("status"); var message="The Value of Provider Block is: " + provider; report.innerHTML = message; }
In firefox, "The Value of Provider Block is: 1:Any Provider" is written in the report element. In IE6, "The Value of Provider Block is : " is written in the report element.
I know the answer must be yes, but I am really having a hard time figuring this out. I have a simple script below, that calculates age (I know I need to do some more work). I want to redisplay the value returned from the function. It works OK, because the result displays correctly in the alert. Code:
I have a form and a submit button .on clicking submit button function validate call.this function call another function (say func) .this func function vallidates some input and return true or false value to the validate function this then return true or false value to the submit button .I want that func directly return true or false to the submit button.
