- New Frequently Asked Questions

irt.org | Knowledge Base | New

• FAQ 1524 Images in a layers disappears in Netscape Navigator on resize
  
  
• FAQ 1525 How to print a certain frame in a frameset from another frame in the same frameset
  
  
• FAQ 1526 Netscape is out of memory, why?
  
  
• FAQ 1527 How do you submit a form by hitting return in a textarea?
  
  
• FAQ 1528 How can I define my own mouse cursor for the Internet Explorer 5 Using my own *.ico file?
  
  
• FAQ 1529 How do I display an image based on the options selected from 3 different menus on the same page?
  
  
• FAQ 1530 How can a text box show the selected item from a select control, and then the select control be reset to always show " Select an item"?
  
  
• FAQ 1531 Is it possible to expire a page using JavaScript with out using tags in the header?
  
  
• FAQ 1532 How can I change the text in the title bar of the browser?
  
  
• FAQ 1533 How can I make a button that moves a table (scrolling effect) up or down?
  
  
• FAQ 1534 How do I use Eastern Standard Time?
  
  
• FAQ 1535 Is it necessary to hide JavaScript code contained in .js source files using the <!-- //--> characters around all the script found in an external file?
  
  
• FAQ 1536 How do I create a Javascript that if it is before a specific time (for example, 9 am) it will display tomorrow's day but will show the day AFTER tomorrow day if it is after that specific time?
  
  
• FAQ 1537 Can I open a popup window with one image in it if one link is clicked, but another image if a different link is clicked?
  
  
• FAQ 1538 Can I set up a textbox where the user can enter and edit the text (Bold, Underline, Font, etc.) without having to enter in HTML code?
  
  
• FAQ 1539 How can I have a realtime character counter for a textarea?
  
  
• FAQ 1540 How can I have a push button that remains pushed in if you push it and released when you push it again (in C++ it call 'radio button style of push button')?
  
  
• FAQ 1541 How can I refresh my main window by clicking on a submit button in a frame of that window?
  
  
• FAQ 1542 How can I print a page without the print dialogue box?
  
  
• FAQ 1543 How can I allow a user, after having checked one of radio buttons, and clicked on an image to move onto a dedicated page depending on chosen radio button?
  
  
• FAQ 1544 How can I provide a translate button to invoke AltaVista's Babel Fish to translate a page from English to French?
  
  
• FAQ 1545 Is it possible to have the close, minimize and maximize functions replaced by clickable images that do the same thing inside a page?
  
  
• FAQ 1546 How can I resize a table through a link, for example: I want to zoom in or zoom out the table when click on a link (zoomIn or ZoomOut). and it would zoom 5 pixels per click?
  
  
• FAQ 1547 How can I open or close four windows using a loop?
  
  
• FAQ 1548 How can I target another window when using radio buttons?
  
  
• FAQ 1549 How do I get a browser to open full screen regardless of the users resolution?
  
  
• FAQ 1550 How to determine whether the user has already selected an option from a multi select list?
  
  
• FAQ 1551 How do I make a box with a list of hyperlinks appear when the mouse cursor hovers over text, as seen at www.microsoft.com?
  
  
• FAQ 1552 How do I disable a form field?
  
  
• FAQ 1553 How can I pass a variable to a function and then sort through a select list to find and remove the option when it is found and also add the option if it is not found?
  
  
• FAQ 1554 How can I download a font to the users computer?
  
  
• FAQ 1555 How can I hide the scrollbars without disabling them?
  
  
• FAQ 1556 How can I ask the user their name and then display it on the page?
  
  
• FAQ 1557 How do I have the browser window center itself on screen regardless of screen resolution?
  
  
• FAQ 1558 How I can change the action of a form depending on the completed text box?
  
  
• FAQ 1559 How can I have a link make the current page the users home page?
  
  
• FAQ 1560 In a form with many text fields, how can you ensure that the form is only submitted if the submit button has been pressed?
  
  
• FAQ 1561 How do I write a link which opens notepad.exe?
  
  
• FAQ 1562 How can I resize a frameset?
  
  
• FAQ 1563 How can I redirect to another page if there is no activity by the user for a certain amount of time?
  
  
• FAQ 1564 Is it possible to generate an array based on the number the user had entered in a text field?
  
  
• FAQ 1565 Is there a way to swap table cell background images from within onMouseEnter?
  
  
• FAQ 1566 When displaying an alert, how can I close the alert box and send the user to a certain page when they click OK?
  
  
• FAQ 1567 How can I download a page in the background of another, or preload the images and sound of a page behind another more simple page, then after a pre determined length of time go to the ready assembled page?
  
  
• FAQ 1568 How can I find the last day of the month for any given month?
  
  
• FAQ 1569 In an object constructor how can I ensure that the correct parameters have been passed?
  
  
• FAQ 1570 How can I use onLoad to check the value of a cookie?
  
  
• FAQ 1571 How can I prevent a popup window being reloaded if the main page is refreshed or reloaded?
  
  
• FAQ 1572 Where can I find FAQs for server-side javascript?
  
  
• FAQ 1573 Is there a way to control the tab-sequence in a form in both Internet Explorer and Netscape Navigator using an array?
  
  
• FAQ 1574 How can I use an array to read in the input for multiple choice radio button questions, and then create a document to display those values by pushing a button?
  
  
• FAQ 1575 What is the Internet Explorer equivalent of Netscape Navigator's window.innerheight and window.innerWidth?
  
  
• FAQ 1576 How can I open a popup window whilst simultaneously changing the URL of the current page?
  
  
• FAQ 1577 How do I detect the browser's color depth and change the background graphic/color accordingly?
  
  
• FAQ 1578 How can I detect, that the user has closed the window (including the use of alt-F4)?
  
  
• FAQ 1579 How can I remove the underline from hypertext links?
  
  
• FAQ 1580 Can I create object getter and setter methods, as I can in Java?
  
  
• FAQ 1581 In Netscape 4 and 4.5 on the Mac, resizing a window causes links in the window to lose their onClick actions
  
  
• FAQ 1582 How can I prevent the browser from loading a certain page if the user won't or can't accept cookies?
  
  
• FAQ 1583 How can I replace all non alphanumeric characters from a string?
  
  
• FAQ 1584 How can I find the remainder or the quotient in a division?
  
  
• FAQ 1585 Is there a way to control the order in which images load?
  
  
• FAQ 1586 Why do you need to include a 'return true' when using mouse overs?
  
  
• FAQ 1587 How do I bookmark a frame using Javascript?
  
  
• FAQ 1588 How can I force the usee to enter data in a text filed if they tab out of an empty text field?
  
  
• FAQ 1589 Does JavaScript support inner functions, in the same way that Java supports inner methods?
  
  
• FAQ 1590 Does JavaScript do 'call by reference' or 'call by value'?
  
  
• FAQ 1591 How can I find out what kind of object a particular form field is?
  
  
• FAQ 1592 Is there a way to retrieve a window's handle given the window's name?
  
  
• FAQ 1593 In the 'onKeyDown' or 'OnKeyPress' event handlers is there a way to retrieve a window's handle given the window's name?
  
  
• FAQ 1594 How can I detect the width of a table?
  
  
• FAQ 1595 How can I disable the "View Source" menu item?
  
  
• FAQ 1596 How can I accept the name of a page to load in a fraemset from the URL?
  
  
• FAQ 1597 Is there a way to launch a window that is 80% of full size, but at least a minimum of, say, 640x480?
  
  
• FAQ 1598 How can I pass text to a function and have it change the selection of a select box to the option which has that text as its value?
  
  
• FAQ 1599 Is it posible to use something like pointers to different objects depending on a condition?
  
  
• FAQ 1600 How do I use the inch sign (") in a string?
  
  
• FAQ 1601 Is there any way to retreive the text from a table cell based on its position in a table (e.g. cell 5,3)?
  
  
• FAQ 1602 How can I make a link inactive (except for a popup window on mouse over) for those browsers which support JavaScript but remain active (clickable) for those browsers which don't?
  
  
• FAQ 1603 How can I use Javascript to stop loading the current page by pressing a button?
  
  
• FAQ 1604 How can I ask a user for input using a prompt and validate whether or not it is a number?
  
  
• FAQ 1605 How can I supply different values to the location object's replace() method, perhaps based on the current date, by invoking a function?
  
  
• FAQ 1606 How can I open a full screen window without any chrome in Netscape Navugator?
  
  
• FAQ 1607 Can JavaScript reference the meta tag name and values in an HTML document, i.e. author, description, keywords?
  
  
• FAQ 1608 From a popup window how can I alter the location of the frame that opened the popup window, plus the location of another sibling frame, and then close the popup?
  
  
• FAQ 1609 Can you use an imagemap with onClick?
  
  
• FAQ 1610 How do I refrence a JavaScript varible in an opener window from the popup window?
  
  
• FAQ 1611 How do I position the cursor on the first field of the first form when a page loads?
  
  
• FAQ 1612 How do I position the cursor on the first field of the first form in the first frame when the frameset loads?
  
  
• FAQ 1613 How can I exit a function in Javascript?
  
  
• FAQ 1614 How can I offer the user the ability to resize the browser to 800x600, and then automatically resize to their original specification when they leave the page?
  
  
• FAQ 1615 Is it possible to detect the browser and use one of two external style sheets?
  
  
• FAQ 1616 How do you generate JavaScript from inside JavaScript?
  
  
• FAQ 1617 How do I exit out of a loop in JavaScript?
  
  
• FAQ 1618 Can swtch statements in JavaScript apply to a range of values?
  
  
• FAQ 1619 How do I get a word count of a string?
  
  
• FAQ 1620 What is the smallest amount of code necessary for image swaping?
  
  
• FAQ 1621 How do I get a word count of the text in a textarea?
  
  
• FAQ 1622 How can i print the active document using Internet Explorer?
  
  
• FAQ 1623 How do I validate that the user has selected one of three radio buttons?
  
  
• FAQ 1624 How can I open a popup window when a visitor clicks a link that leaves my site?
  
  
• FAQ 1625 How can I cause a page to refresh/reload when a user changes the size of the window?
  
  
• FAQ 1626 How can prevent a window from being resized in one direction only?
  
  
• FAQ 1627 How can I ensure that all the buttons on are form are all clicked before allow the submit button to submit the form?
  
  
• FAQ 1628 How can I preload an animated image, but ensure that it animates once the page has completely loaded?
  
  
• FAQ 1629 How can I prevent more than four checkboxes being clicked?
  
  
• FAQ 1630 How can I find the major and minor version of the JavaScript support in Internet Explorer?
  
  
• FAQ 1631 How can I chec that a frame that holds a function that I want to invoke has loaded the function successfully?
  
  
• FAQ 1632 How do I close a window opened by a frame when a new page loads into the creating frame?
  
  
• FAQ 1633 Is it possible to start Internet Explorer with an index.html page loaded fullscreen without toolbars?
  
  
• FAQ 1634 If I have frames is there a way to delete one of them from a button in another frame?
  
  
• FAQ 1635 Can I prefill a text form field with the current date?
  
  
• FAQ 1636 How can I stop a user from hitting the Submit button twice?
  
  
• FAQ 1637 How can I get the first 200 characters from a text string?
  
  
• FAQ 1638 How can I disable the Internet Explorer auto complete form field feature?
  
  
• FAQ 1639 Is it possible to scroll in layers in Netscape?
  
  
• FAQ 1640 How can I replace a frameset with a single page after a delay?
  
  
• FAQ 1641 Can I maximize the current popup window by clicking on the link in that same window?
  
  
• FAQ 1642 Can I share JavaScript and VBScript variables on the same page?
  
  
• FAQ 1643 How can I extract all the selected options from a multiple selection list?
  
  
• FAQ 1644 How do you have a user enter a password, then re-enter the password to be verified?
  
  
• FAQ 1645 How can I make an image blink on and off a specified number of times?
  
  
• FAQ 1646 How can I ensure that four and only four checkboxes being clicked in a form?
  
  
• FAQ 1647 How do I force Internet Explorer to print an HTML page as landscape rather than portrait?
  
  
• FAQ 1648 Is there a way to invoke a server side process without affecting the current page being displayed when the user interacts with a form?
  
  
• FAQ 1649 How can I show the next seven days in a drop down list?
  
  
• FAQ 1650 How can I make an animation whereby each individual image, when clicked, links to a different url?
  
  
• FAQ 1651 Is there any way to detect whether Internet Explorer users have a Flash Plugin?
  
  
• FAQ 1652 What is the story behind JavaScript, i.e. its history?
  
  
• FAQ 1653 How can I compare two strings to ensure they are equal?
  
  
• FAQ 1654 Is it possible to print a popup window?
  
  
• FAQ 1655 How can I read the contents of another HTML page?
  
  
• FAQ 1656 Can I make an array of functions?
  
  
• FAQ 1657 Is it possible to auto-refresh an image every X seconds?
  
  
• FAQ 1658 How do I automatically insert a character after every Nth character in a string?
  
  
• FAQ 1659 How can I scroll another frame?
  
  
• FAQ 1660 Is it possible to add a property or a method to pre-built objects, such as Image objects?
  
  
• FAQ 1661 How can I tell when a inline frame has finished loading?
  
  
• FAQ 1662 Is there a way to restrict number of characters within a textarea?
  
  
• FAQ 1663 How can I pass multiple selected options from a select list to a popup window?
  
  
• FAQ 1664 How do you get sound to work on mouse over in both Internet Explorer and Netscape Navigator?
  
  
• FAQ 1665 What is the difference between square brackets, i.e. [], and parenthesis', i.e. ()?
  
  
• FAQ 1666 How can I ensure that a user has checked button, and has selected an item from a select list?
  
  
• FAQ 1667 Is it possible to prompt the user for two values?
  
  
• FAQ 1668 In Internet Explorer 4 if I press the backspace key, and no element has focus, it behaves as if the history back button was clicked, how do I trap this event and disable it?
  
  
• FAQ 1669 How can I write into a Netscape Navigator 4 layer without specifying an absolutely positioned layer?
  
  
• FAQ 1670 Can you change the values of form fields when a checkbox is clicked?
  
  
• FAQ 1671 How can I prevent an external JavaScript file from loading until called for by the click of a button?
  
  
• FAQ 1672 When a page reloads (due to the user pressing back) how do I clear a form of all the user entered data?
  
  
• FAQ 1673 When capturing a userid and password in a form can I subsequently use them when requesting a server page that requires HTTP authentication?
  
  
• FAQ 1674 How do I change text to bold using JavaScript?
  
  
• FAQ 1675 Is it possible to hide the URL of a link using on mouse over?
  
  
• FAQ 1676 How do I submit a form in Frame A from Frame B?
  
  
• FAQ 1677 How can I redirect to another page if there is no activity by the user for a certain amount of time?
  
  
• FAQ 1678 Is there a way to allow single clicks but prevent double clicks?
  
  
• FAQ 1679 How do i perform E-mail validation?
  
  
• FAQ 1680 How can I dock one popup window to the side of another?
  
  
• FAQ 1681 How can I close an entire frameset with with a button link or text link?
  
  
• FAQ 1682 How can I open or close multiple windows using a loop?
  
  
• FAQ 1683 Is there any way for a parent window to check if a child window has fully loaded?
  
  
• FAQ 1684 How can I round to two decimal places, but without losing any zeros in the answer?
  
  
• FAQ 1685 How do I get the IP address of the visitor?
  
  
• FAQ 1686 How can I generate a page in JavaScript when a button is pressed that both replaces the current page in the browser's history, and cannot be linked to directly?
  
  
• FAQ 1687 How do you make a generic function to change the image at on mouse out and on mouse over events which can be accessed from anywhere in the document just by specifiying the names of the images to change?
  
  
• FAQ 1688 How do I find the number of days in a month (or last day of a month)?
  
  
• FAQ 1689 Why in Netscape Navigator when using tables with the bgcolor parameter, my radio buttons show a box around them?
  
  
• FAQ 1690 How can I swap a larger image for a smaller image and vice versa?
  
  
• FAQ 1691 Q736 Is there any way to emulate a onDblClick event hander for browsers that don't
  
  
• FAQ 1692 How do I apply the title of a page that gets loaded inside a frame to the top frame?
  
  
• FAQ 1693 Is it possible to stop a form from submitting when enter is pressed?
  
  
• FAQ 1694 How can I change a selected item in one select box based on a choice from another select box without using frames?
  
  
• FAQ 1695 How can I change a selected item in one select box based on a choice from another select box without using frames?
  
  
• FAQ 1696 How can I update the action attribute of a form to include details from one of the form fields?
  
  
• FAQ 1697 How do I load specific pages into specific frames of an existing frameset site, when the current page is not in a frameset?
  
  
• FAQ 1698 How can I extract just the extension file name from a forms file upload field?
  
  
• FAQ 1699 How can I create a fixed length String Buffer that I can append text to?
  
  
• FAQ 1700 How can I create a single frame frameset?
  
  
• FAQ 1701 How can I get the value of a text input field without using the name of the field?
  
  
• FAQ 1702 How can I use an external JavaScript source file to amend all the mailto links in a document such that it appends a generic subject line?
  
  
• FAQ 1703 How can I clear the contents of one frame from another?
  
  
• FAQ 1704 How can I performance test JavaScript?
  
  
• FAQ 1705 Can I submit a form in a parent window by clicking a submit button in a child window?
  
  
• FAQ 1706 How can I randomly open one of 100 windows named 1.htm to 100.htm?
  
  
• FAQ 1707 How can I completely hide a frame in all browsers?
  
  
• FAQ 1708 How can I pass the value of a hidden field into a confirm dialog box when the submit button is pressed, so I can ask the user if they really want to edit/remove the visible version of the hidden value?
  
  
• FAQ 1709 How can I use the main windows scrollbars to scroll the contents of an inline frame?
  
  
• FAQ 1710 How do I ensure that a form field contains a .gov domain (whether that be .gov, .gov.uk etc)?
  
  
• FAQ 1711 How can set the focus in a form field in a absolutelty positioned layer?
  
  
• FAQ 1712 How can I disable a group of radio buttons?
  
  
• FAQ 1713 How can I send the submission of an from to an email address or a URL depending of the status of a checkbox?
  
  
• FAQ 1714 How can I resize the opener of a popup window?
  
  
• FAQ 1715 How can I concatenate two values from two select lists to the URL associated with a clicked image map?
  
  
• FAQ 1716 How can I detect when the opener of a popup window has changed?
  
  
• FAQ 1717 How do I check that text entered in a text form field is an integer?
  
  
• FAQ 1718 How can I reject a form submission if one of any number of validate functions returns false?
  
  
• FAQ 1719 How can I populate a list of text form fields from the selected options in a multiple select list?
  
  
• FAQ 1720 How can I copy the contents pf a text input form field when the user changes its value to a hidden form field in a different form on the same page?
  
  
• FAQ 1721 How can I round up a number to the nearest 0.5?
  
  
• FAQ 1722 How can I force an unclicked link to look as though it had been clicked?
  
  
• FAQ 1723 How can I redirect to another page depending on how many checkboxes have been checked?
  
  
• FAQ 1724 How can I dynamically display text underneath an image using an image map and on mouse over events?
  
  
• FAQ 1725 How do I avoid the main window displaying [object] when I click on a hypertext link to open a new popup window?
  
  
• FAQ 1726 How can I count of number of instances of a particular word or character in a string?
  
  
• FAQ 1727 How can I hint to the user that I want a password enter into a text field, and then when the user enters text into the field it turns into a password field?
  
  
• FAQ 1728 How can I show the dates for the last two weeks in a select form field?
  
  
• FAQ 1729 How can I uncheck all radio boxes within a group of radio boxes?
  
  
• FAQ 1730 How can I remove options from a select list based either on the text property value or the value property value?
  
  
• FAQ 1731 Is there a way of shifting the contents of an array down / up e.g. 1 becomes 2, 2 becomes 3 etc?
  
  
• FAQ 1732 How can I display an absolutely positioned layer of content over form fields so that the form fields do not show through the layer?
  
  
• FAQ 1733 How do you dynamically write a form field to a layer so Netscape displays it?
  
  
• FAQ 1734 How can I display something on the page if JavaScript is disabled without first testing from another page?
  
  
• FAQ 1735 How can an imagemap capture the focus when the mouse moves over a hotspot?
  
  
• FAQ 1736 Why does document.myForm.submit() not work or return an error?
  
  
• FAQ 1737 On Netscape 4.0 & 4.6 for the Mac resizing the window will break all of your hyperlinks' onClick actions
  
  
• FAQ 1738 How can a function in one *.js file call another function in a second *.js file?
  
  
• FAQ 1739 How can I make the page longer, or the vertical scroll bar appear when I dynamically populate a layer with lots of content in Netscape Navigator 4?
  
  
• FAQ 1740 How can I filter user input to leave just the numerical digits?
  
  
• FAQ 1741 Is it possible to put a scrollbar to a select drop down list?
  
  
• FAQ 1742 Can you simulate a click on an <input type="file"> button?
  
  
• FAQ 1743 When placing the value of a JavaScript variable into a URL request, how do I correctly format the variable value, so that spaces etc are converted into the standard html request syntax?
  
  
• FAQ 1744 How can cross-hairs follow the mouse pointer over an image or set of images?
  
  
• FAQ 1745 How can an image slide across the top of images when the mouse pointer moves across the same images?
  
  
• FAQ 1746 Is it possible to secure web pages using JavaScript?
  
  
• FAQ 1747 How can I change the HREF attribute of a link when a form button is clicked?
  
  
• FAQ 1748 Netscape Navigator 4 loses the onMouseDown event handlers after a window resize
  
  
• FAQ 1749 How can I assign five substrings of a larger string to the variables named str1, str2... to str5?
  
  
• FAQ 1750 How do I test the equality of two strings?
  
  
• FAQ 1751 Why do animated GIFs stop animating when I click on a link, and how can I avoid this?
  
  
• FAQ 1752 Can JavaScript use newline characters to format the output?
  
  
• FAQ 1753 How do you determine if a variable exists?
  
  
• FAQ 1754 How can I execute a function every 10 seconds?