|
JavaScript - Empty Array Elm Type?
What type of variable is an empty array element?
i thought it was undefined, but i noticed that they have different behavior than undefined does: Code: var r=Array(1); var s=r.concat([0,"",null,undefined]); alert (s.toSource()) //==="[, 0, "", null, (void 0)]" typeof s[0] //==="undefined" typeof s[4] //==="undefined" as you can see, 0 and 4 both === undefined. yet, they don't have the same toSource()... why? is this special type named anything specific? or more importantly, can it be detected outside of an array as being distinct from undefined? EDIT: im thinking this would be the same type as ({}).nonProp ... i guess the question is actually, "can you tell the difference between uninitialized and undefined"? Similar TutorialsHow do i declare an empty array? I need to iterate through a group of arrays and search for a user-chosen word every time. The problem is i can't declare how many array elements will be needed, such as: new array = (12), because some words inside my arrays, occur more than others. So i need to decalare an empty array with x number of possible values. Can this be done? Is there a built in method to remove empty array elements
anotherVar should be -1 if there are no matches, but it doesn't seem to work
PHP Code: var string = "abadafa"; var matches = string.match(/a/gi); //doesn't work with /z/ for example var anotherVar = matches.length || -1; The default operator should return the second value if the first is null or false, and according to PHP Code: try { alert(matches.length); } catch (e){ alert(e); //alerts null } it's null. fyi: http://helephant.com/2008/12/javascr...ault-operator/ What's going on? php has the $_POST GLOBAL that contains an array of all the POST form variables. Does Javascript contain something similar built in?
I need to change input type="text" to input type="password" via JavaScript Code: <form id="login" action="#" method="post"> <input id="username-field" type="text" name="username" title="Username" onmousedown="javascript:this.value=''; javascript:this.focus();" value="Username" tabindex="1" /> <input id="password-field" type="text" name="password" title="Password" onmousedown="javascript:this.value=''; javascript:this.type='password'; javascript:this.focus();" value="Password" tabindex="2" /> <input type="submit" name="submit" value="sign in" tabindex="3" /> </form> This works in Firefox and Safari but not IE So then I tried this code Code: <script type="text/javascript">
function passit(ip){
var np=ip.cloneNode(true);
np.type='password';
if(np.value!=ip.value)
np.value=ip.value;
ip.parentNode.replaceChild(np,ip);
}
</script>
<form id="login" action="#" method="post">
<input id="username-field" type="text" name="username" title="Username" onmousedown="javascript:this.value=''; javascript:this.focus();" value="Username" tabindex="1" />
<input id="password-field" type="text" name="password" title="Password" onmousedown="javascript:this.value=''; passit(this.form[0]); javascript:this.focus();" value="Password" tabindex="2" />
<input type="submit" name="submit" value="sign in" tabindex="3" />
</form>
This does what I need but turns the username type to password field not the password box Please can somone help! Hello I am building a registration page . If the user completes all the required field i load the info into the database but if there are missing fields I combined some javascript into php to display next to the empty field a note that it should be filled. This is my code : Code: <?php
if (isset($_POST['submit']))
{
$username =$_POST['username'];
$password =$_POST['password'];
$password2 =$_POST['password2'];
$firstname =$_POST['firstname'];
$lastname =$_POST['lastname'];
$email =$_POST['email'];
$address =$_POST['address'];
$city =$_POST['city'];
$state =$_POST['state'];
$zip =$_POST['zip'];
$dob =$_POST['dob'];
if (empty($username)){
?> <script language="javascript">
var user =true
</script> ;<?
}
if (empty($password)){
?> <script language="javascript">
var pass =true
</script><? ;
}
And it goes on................... Then next to the inpput box I display a text in case the user didn't fill in the info like this and by the way the above code is in my validate.php page wich i include in the main registration page Code: <?php include ('includes/validate.php');?>
<form action="registration.php" method= "post" >
<fieldset>
<legend>sitename Registration</legend>
<p>
<label for"username">Username</label>
<input type "text" name=username /> <script type="text/javascript">
if (user == true)
{
document.write("Please enter a Username of your choice");
}
</script>
</p>
<p>
<label for"password">Password</label>
<input type "password" name=password /> <script type="text/javascript">
if (pass == true)
{
document.write("Please choose a Password");
}
</script>
</p>
<p>
<label for"password2">Re-type Password</label>
<input type "pass2" name=password2 /> <script type="text/javascript">
if (pass2 == true)
{
document.write("Please re-type your Password");
}
</script>
</p>
And it goes on......for the rest of the input fields. I need some help with a solution for when the user fills in the info and pushes the "register" button the page refreshes and it whipes all the info the user already input but it does display the warnings where the user didn't input any data, so what would be the best way to go to keep the data that the user entered.Thank you. Hey guys, Is there a way of hiding a whole table row if a certain cell inside it is empty? Thanks, Adam Hi i would like to know how to check for any check boxes that are empty if any is empty then i want the code to stop were its at and go no ferther and prompt a message somthing missing?
Hello, I'm trying to compare a <div> background color with another color. However, on FireBug, I noticed that my <div> doesn't have a background color code in it (I placed document.getElementById(o) on watch), even though I have already specified on my css. As a result, I'm comparing an empty string with another color code. Why is this so ? Javascript: Code: function highlight(o) {
var color1;
color1 = document.getElementById(o).style.backgroundColor;
if (color1.compareColor("#0072BC")) {
document.getElementById(o).style.backgroundColor="#f8951e";
}
else if(color1.compareColor("#f8951e")){
document.getElementById(o).style.backgroundColor="#0072BC";
}
}
HTML: Code: <div class="nav-tab" id="home"><a href="#" onmouseover="highlight('home')" onmouseout="highlight('home')" >Home</a></div>
Tearing my hair out here. I've got a table where I'm trying to append additional input and file fields when someone clicks a link. The appending works fine, but when I click submit, none of the appended values are being passed through. I've tried it two different ways (both being appended to the "moreSwatches" table cell: Code: function addSwatch2()
{
var moreSwatches = document.getElementById('moreSwatches');
imgBox = document.createElement("input");
//imgBox.type = 'file';
//imgBox.name = 'swatch[]';
imgBox.setAttribute("type","file");
imgBox.setAttribute("name","swatch[]");
moreSwatches.appendChild(imgBox);
textBox = document.createElement("input");
textBox.type = 'text';
textBox.name = 'swatchname[]';
moreSwatches.appendChild(textBox);
setBR = document.createElement("br");
moreSwatches.appendChild(setBR);
}
function addSwatch()
{
var moreSwatches = document.getElementById('moreSwatches');
var newDiv = document.createElement("div");
addText = '<input type="file" name="swatch[]" style="width: 300px"> <input name="swatchname[]" size="25"><br>';
newDiv.innerHTML = addText;
moreSwatches.appendChild(newDiv);
}
If I hardcode a second set of inputs below the first, it works fine. Anything that is appended is getting ignored. Anyone got any ideas? Hey folks. I currently have a PTZ camera that is taking screenshots every minute (or so) and sending a copy of that image (overwriting the previous one) to my website. Basically, the visitors to the website will be greeted with a live screenshot. The problem is if the visitor hits the website at just the right time, the screenshot won't be loaded completely while the 2nd most screenshot is being overwritten... creating an empty image load (the dreaded red X). What I am looking to do with Javascript is to be able to load a generic image in the scenario in which no image loads. Is that possible? I tried doing something like the following and onload-ing it, but it wouldn't work. Any help would be appreciated. Thanks! Code: <script type="text/javascript">
<!--
function replaceSrc() {
var images = document.getElementsByTagName('img');
for(var i = 0; i < images.length; i++) {
var img = images[i];
if(img.src.length == 0) {
img.src = 'images/garbage.gif';
}
}
}
-->
</script>
Hi. I have a form and if a field is blank a message pops up. This doesnt stop my php from running though and takes the user to another page. Is there a line to keep them on that page untill all fields are filled out? code so far is simple. <script type="text/javascript" language="JavaScript"> function nameempty() { if ( document.form.subject1.value == '' ) { alert('No name was entered!') return false; } } </script> //then down the bottom I have a small bit that implements that code How to get this to work? Code: <html> <body> <script type="text/javascript" src="01.js"> <h1>Welcome</h1> <a href="#" onclick="write(); return false;">Click here</a> <div id="info_here"> </div> </body> </html> 01.js Code: function write() {
var a=document.getElementById("info_here");
a.innerHTML=document.write("Hello <br />" + "Thanks for clicking");
}
Hi, I am not able to calculate the offsetwidth of the element which contains extra space in between the characters. for ex. if the element contains "A A" as a innerHTML value - if we calculate offsetwidth as 29 and also if the element contains "A A" value again I am getting the same offsetwidth as 29. While calculating the offsetwidth it is not calculating the empty space. May I know how to calculate the offsetwidth with the empty space because I need to insert the ellipsis (...) if it exceeds original width? Code snipet function fitStringToWidth(title,width,className) { var span = document.createElement("span"); span.className="titleBar-Title-1"; span.style.display='inline'; span.style.visibility = 'hidden'; span.style.padding = '0px'; document.body.appendChild(span); var result = title; span.innerHTML = result; alert("Offsetwidth : " + span.offsetWidth); .......................... } Thanks in advance. Arthik Hi guys, I am using jquery ui to have two connected sortable lists. The first list is available numbers, and the second is selected numbers. Everything with the jquery is working fine. The problem i am having is when i try to get the contents of the selected numbers box, it is empty, even though the sortables are or were dragged to that list. I tried using this... Code: var response = $("#selected_numbers_box").val();
alert( response );
and I also tried this.. Code: var response = $("#selected_numbers_box").html();
alert( response );
both are empty. What i am trying to do is retrieve the values of the new list "Selected numbers Box". Any suggestions? My code was taken directly from the jquery ui tutorial. Thanks in advance. Hi there, I have this form that validates a few textboxes & a dropdownlist. And when it is not filled in, the border of the textboxes and dropdownlist would turn red, followed by an alert message notifying which field have not been filled in. Else, the border will revert back to black, and the form will be submitted successfully. Right now, I would like to prevent the user from entering blanks (like entering a space to cheat the system). How should I tweak the codes to make it work? Javascript Code: function check(checkForm)
{
var fields = new Array("Name","Email Address", "Domain Name");
var index = new Array(),k=0;
for(var i=0;i<fields.length;i++)
{
var isFilled = false;
var c = document.getElementsByName(fields[i]);
for(var j = 0; j < c.length; j++)
if(!c[j].value == "")
{
isFilled = true;
c[j].className = "defaultColor";
}
else
{
c[j].className ="changeToRed";
}
if(!isFilled)
{
index[k++] = fields[i];
}
}
if(k>0)
{
joinComma = index.join(', ');
alert('The field(s) corresponding to '+ joinComma + ' is/are not selected.');
return false;
}
}
HTML Code: * Name: <input type="text" id="Text27" name="Name" /><br /> <br /> *Email Address: <input type="text" id="Text28" name="Email Address" /> @ <select id="Select5" name="Domain Name"> <option></option> <option>hotmail.com</option> <option>yahoo.com</option> </select> <input id="Submit5" type="submit" value="Submit" onclick="return check(checkForm)"/> Hi. I have a form and in the form is a checkbox use as a switch to hide and unhide a two textbox. When the other textbox is hide, the other is unhide such as the code below. When the user click the submit button on the first time and there is an error, it reloads and the id="fieldset.-in_honor" hide because it is set to hide initially but not empty. My problem is, I want to show the fieldset whichever is not empty after submit button is click and there is an error so user will not enter any more information to the other field. Is that possible? Please help. I have a hard time explaining it but hopefully you will get the idea. Thanks in advance and hope to hear from you as soon as possible. Code: /*toggle switch*/
<p><input type="checkbox" name="in_honor" value="" id="checkmemoriam" onclick="showHide(this.name);" />Please check to make this donation in honor of someone special.</p>
/*hide textbox but unhide when the switch is on or the checbox is check*/
<fieldset id="fieldset-in_honor" class="fieldgroup" style="display:none">
<legend class="hide">In Honor Of</legend>
<p>To make this donation in honor of someone special, please complete the two fields below:</p>
<div class="formfield" <?php echo highlight('donate_honor_name'); ?>>
<label for="donate_honor_name">Name:</label>
<input id="donate_honor_name" name="donate_honor_name" class="text" type="text" value="<?php safeEcho($form['donate_honor_name'])?>" />
<?php helper_error('donate_honor_name'); ?>
</div>
<div class="formfield" <?php echo highlight('donate_honor_acknowledgement'); ?>>
<label for="donate_honor_acknowledgement">Acknowledgement should be sent to:</label>
<textarea id="donate_honor_acknowledgement" name="donate_honor_acknowledgement"><?php safeEcho($form['donate_honor_acknowledgement'])?></textarea>
<?php helper_error('donate_honor_acknowledgement'); ?>
</div>
/*always show on first load of the page but once the checkbox is check, will need to hide and delete info entered*/
<fieldset id="fieldset-in_registration">
<label for="impact" style="font-weight:bold">B. Impact Areas</label>
<table>
<tr>
<td style="width:380px;text-align:left"><label for="d" id="deslist4" name="deslist4">Crime and Drug Use <a href="javascript:alert('Ensuring prevention and treatment programs and appropriate support services are available to people who are at risk for drug addiction and supporting efforts to reduce crime.');">what is this?</a></label></td>
<td style="float:right"> $<input id="d" name="d" class="text" type="text" value="<?php safeEcho($form['d'])?>" style="width:90px;" onChange="CalculateTotal()" />
<?php helper_error('d');?> </td>
</tr>
<tr>
<td style="width:380px;text-align:left"><label for="e" id="deslist5" name="deslist5">Early Childhood Development <a href="javascript:alert('Children are healthy, loved, nurtured, safe and have access to quality childcare and early education. This includes programs that increase parenting skills, providing books to all children and providing developmental screening for 3 and 4 year olds.');">what is this?</a></label></td>
<td style="float:right"> $<input id="e" name="e" class="text" type="text" value="<?php safeEcho($form['e'])?>" style="width:90px;" onChange="CalculateTotal()" />
<?php helper_error('e');?> </td>
</tr></table>
Code: /*JAVASCRIPT FUNCTION*/
function showHide()
{
if (document.getElementById('checkmemoriam').checked)
{
if (document.getElementById('TotalC').value == "0.00")
{
document.getElementById('fieldset-in_honor').style.display=""; // this is for showing
document.getElementById('fieldset-in_registration').style.display="none";
}
else
{
var answer = confirm("You entered a total gift designation of $" + document.getElementById('TotalC').value + ". At this time, gifts made \"in honor of someone special\" are not eligible for the designation option. Clicking the OK button will delete all your designation(s). Do you want to continue?")
if (answer)
{
document.getElementById('TotalC').value="0.00";
document.getElementById('d').value="0";
document.getElementById('e').value="0";
document.getElementById('fieldset-in_honor').style.display=""; // this is for hiding
document.getElementById('fieldset-in_registration').style.display="none";
}
else
{
document.getElementById('checkmemoriam').checked=false;
}
}
}
else
{
if ((document.getElementById('donate_honor_name').value="") && (document.getElementById('donate_honor_acknowledgement').value=""))
{
document.getElementById('fieldset-in_honor').style.display="none"; // this is for hiding
document.getElementById('fieldset-in_registration').style.display="";
}
else
{
var answer = confirm("The field you are trying to close will delete all information you entered \"in honor of someone special\" but it will allow you to designate. Clicking the OK button will show the designation list. Do you still want to continue?")
if (answer)
{
document.getElementById('donate_honor_name').value = "";
document.getElementById('donate_honor_acknowledgement').value = "";
document.getElementById('fieldset-in_honor').style.display="none"; // this is for hiding
document.getElementById('fieldset-in_registration').style.display="";
}
else
{
document.getElementById('checkmemoriam').checked=false;
document.getElementById('fieldset-in_honor').style.display=""; // this is for showing
document.getElementById('fieldset-in_registration').style.display="none";
}
}
}
}
Hi there, I am having a hard time trying to understand this: The script I am using does not work if I write doctype as follows: Code: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> But it does when removing the link: Code: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" > However when I remove the link from the doc type, in IE my selected menu is unaligned; Here is the link. Have you got an idea about why it does not work with the full doc type? Thanks a lot for having a look; Hi, As part of a package deal I received a javascript script for redirecting a webpage. Now I already have simple redirection but wanted to see how this one did the redirection. But it starts off by defining an array with strange sets of characters. Is this hexadecimal or something ? Can I convert it into a more readable and understandable form ? var _0x46d5=["\x67\x65\x74\x54\x69\x6D\x65","\x73\x65\x74\x54\x69\x6D\x65","\x3B\x20\x65\x78\x70\x69\x72\x65\x73\ x3D","\x74\x6F\x47\x4D\x54\x53\x74\x72\x69\x6E\x67","","\x63\x6F\x6F\x6B\x69\x65","\x3D","\x3B\x20\x 70\x61\x74\x68\x3D\x2F","\x3B","\x73\x70\x6C\x69\x74","\x6C\x65\x6E\x67\x74\x68","\x73\x75\x62\x73\x 74\x72\x69\x6E\x67","\x63\x68\x61\x72\x41\x74","\x20","\x69\x6E\x64\x65\x78\x4F\x66","\x26","\x3F"," \x68\x72\x65\x66","\x6C\x6F\x63\x61\x74\x69\x6F\x6E","\x73\x6C\x69\x63\x65","\x70\x75\x73\x68","\x65 \x7A\x6D\x62\x72\x65\x64","\x4E","\x59","\x75\x73\x65\x72\x41\x67\x65\x6E\x74","\x76\x65\x6E\x64\x6F \x72","\x6F\x70\x65\x72\x61","\x74\x65\x73\x74","\x73\x75\x62\x73\x74\x72"]; function createCookie(_0x810ex2,_0x810ex3,_0x810ex4,_0x810ex5){ ... the script continues using the array elements above. Thanks for any insights. . In this code, what does the beginning "setCal ()" do, and what is it? Its not a function, or a variable, I'm confused... Code: <script>
/*Copyright 1996 - Tomer and Yehuda Shiran
Feel free to "steal" this code provided that you leave this notice as is.
Additional examples from the book can be found at http://www.geocities.com/SiliconValley/9000/
For more information contact Tomer or Yehuda Shiran <yshiran@iil.intel.com>*/
setCal()
function getTime() {
// initialize time-related variables with current time settings
var now = new Date()
var hour = now.getHours()
var minute = now.getMinutes()
now = null
var ampm = ""
// validate hour values and set value of ampm
if (hour >= 12) {
hour -= 12
ampm = "PM"
} else
ampm = "AM"
hour = (hour == 0) ? 12 : hour
// add zero digit to a one digit minute
if (minute < 10)
minute = "0" + minute // do not parse this number!
// return time string
return hour + ":" + minute + " " + ampm
}
function leapYear(year) {
if (year % 4 == 0) // basic rule
return true // is leap year
/* else */ // else not needed when statement is "return"
return false // is not leap year
}
function getDays(month, year) {
// create array to hold number of days in each month
var ar = new Array(12)
ar[0] = 31 // January
ar[1] = (leapYear(year)) ? 29 : 28 // February
ar[2] = 31 // March
ar[3] = 30 // April
ar[4] = 31 // May
ar[5] = 30 // June
ar[6] = 31 // July
ar[7] = 31 // August
ar[8] = 30 // September
ar[9] = 31 // October
ar[10] = 30 // November
ar[11] = 31 // December
// return number of days in the specified month (parameter)
return ar[month]
}
function getMonthName(month) {
// create array to hold name of each month
var ar = new Array(12)
ar[0] = "January"
ar[1] = "February"
ar[2] = "March"
ar[3] = "April"
ar[4] = "May"
ar[5] = "June"
ar[6] = "July"
ar[7] = "August"
ar[8] = "September"
ar[9] = "October"
ar[10] = "November"
ar[11] = "December"
// return name of specified month (parameter)
return ar[month]
}
function setCal() {
// standard time attributes
var now = new Date()
var year = now.getYear()
if (year < 1000)
year+=1900
var month = now.getMonth()
var monthName = getMonthName(month)
var date = now.getDate()
now = null
// create instance of first day of month, and extract the day on which it occurs
var firstDayInstance = new Date(year, month, 1)
var firstDay = firstDayInstance.getDay()
firstDayInstance = null
// number of days in current month
var days = getDays(month, year)
// call function to draw calendar
drawCal(firstDay + 1, days, date, monthName, year)
}
function drawCal(firstDay, lastDate, date, monthName, year) {
// constant table settings
var headerHeight = 50 // height of the table's header cell
var border = 2 // 3D height of table's border
var cellspacing = 4 // width of table's border
var headerColor = "midnightblue" // color of table's header
var headerSize = "+3" // size of tables header font
var colWidth = 60 // width of columns in table
var dayCellHeight = 25 // height of cells containing days of the week
var dayColor = "darkblue" // color of font representing week days
var cellHeight = 40 // height of cells representing dates in the calendar
var todayColor = "red" // color specifying today's date in the calendar
var timeColor = "purple" // color of font representing current time
// create basic table structure
var text = "" // initialize accumulative variable to empty string
text += '<CENTER>'
text += '<TABLE BORDER=' + border + ' CELLSPACING=' + cellspacing + '>' // table settings
text += '<TH COLSPAN=7 HEIGHT=' + headerHeight + '>' // create table header cell
text += '<FONT COLOR="' + headerColor + '" SIZE=' + headerSize + '>' // set font for table header
text += monthName + ' ' + year
text += '</FONT>' // close table header's font settings
text += '</TH>' // close header cell
// variables to hold constant settings
var openCol = '<TD WIDTH=' + colWidth + ' HEIGHT=' + dayCellHeight + '>'
openCol += '<FONT COLOR="' + dayColor + '">'
var closeCol = '</FONT></TD>'
// create array of abbreviated day names
var weekDay = new Array(7)
weekDay[0] = "Sun"
weekDay[1] = "Mon"
weekDay[2] = "Tues"
weekDay[3] = "Wed"
weekDay[4] = "Thu"
weekDay[5] = "Fri"
weekDay[6] = "Sat"
// create first row of table to set column width and specify week day
text += '<TR ALIGN="center" VALIGN="center">'
for (var dayNum = 0; dayNum < 7; ++dayNum) {
text += openCol + weekDay[dayNum] + closeCol
}
text += '</TR>'
// declaration and initialization of two variables to help with tables
var digit = 1
var curCell = 1
for (var row = 1; row <= Math.ceil((lastDate + firstDay - 1) / 7); ++row) {
text += '<TR ALIGN="right" VALIGN="top">'
for (var col = 1; col <= 7; ++col) {
if (digit > lastDate)
break
if (curCell < firstDay) {
text += '<TD></TD>';
curCell++
} else {
if (digit == date) { // current cell represent today's date
text += '<TD HEIGHT=' + cellHeight + '>'
text += '<FONT COLOR="' + todayColor + '">'
text += digit
text += '</FONT><BR>'
text += '<FONT COLOR="' + timeColor + '" SIZE=2>'
text += '<CENTER>' + getTime() + '</CENTER>'
text += '</FONT>'
text += '</TD>'
} else
text += '<TD HEIGHT=' + cellHeight + '>' + digit + '</TD>'
digit++
}
}
text += '</TR>'
}
// close all basic table tags
text += '</TABLE>'
text += '</CENTER>'
// print accumulative HTML string
document.write(text)
}
</script>
<p align="center"><font face="arial" size="-2">This free script provided by</font><br>
<font face="arial, helvetica" size="-2"><a href="http://javascriptkit.com">JavaScript
Kit</a></font></p>
|
|||||||