Need HTMLElement API: click() equivalent for IE6+ - javascript

Hi I am trying to trigger a click event when enter key is pressed but i'm not sure of a way to do it for ie6

Maybe this:
if (document.attachEvent) {
document.attachEvent("keypress", function(e) {
var keyCode = e.which || e.keyCode
if (keyCode === 13) document.getElementById("button1").click()
})
}

If you really need to do this on IE6, there you go (make sure this is run in IE<9 only):
var input = document.getElementById('some_input'), // Presumably an input element
element = document.getElementById('some_element'); // The element to click
input.attachEvent('onkeydown', function (e) {
if (e.keyCode != 13) {return;} // Quit, no ENTER pressed
element.click();
// Prevents the default action of the event
e.cancelBubble = true;
e.returnValue = false;
return;
});
keydown needs to be listened, since keypress doesn't detect ENTER, and keyup is not cancelable. If the element ENTER was pressed on, is input element, you've to prevent the default action to prevent a form being submitted. Some early IE versions submitted a form on the page even when the input was outside of the form. If the element you're going to hit ENTER is not an input element, or you don't have any forms on the page, the default action preventing is not needed.

Related

Capture TAB keydown and trigger other keypress

I am trying to change the behaviour of selects in an html form.
I would like that when a user navigates the form using the keyboard, if they are selecting an element and presses tab, the element is selected and the focus switches to the next form input. Normally, you need to press enter to select the element and then you can use tab to switch to the next one. If enter isn't pressed, no option is selected.
To do this, I want to capture the TAB keypress and trigger an ENTER keypress followed by a TAB.
This is what I have for now:
$('form[class="ui form"]').on('keydown', 'div[class="ui fluid selection dropdown active visible"]', function (e) {
var keyCode = e.keyCode || e.which;
if (keyCode == 9) {
e.preventDefault();
var y = jQuery.Event('keydown', {which: 13});
$(this).trigger(y);
var x = jQuery.Event('keydown', {which: 9});
$(this).trigger(x);
}
});
Here is a demo: JSFiddle
The code 'works' up to e.preventDefault(), the tab keypress doesn't switch the focus to the next input. However, the enter and tab actions aren't triggered, so nothing happens. What should I do ?
Thank you in advance !
UPDATE 10/10: Found the problem! Triggering event x (tab keypress) makes the code enter an infinite loop. Therefore the whole approach is wrong. I'll soon post an answer.
When I try it passing whichas the event object, it does work jsfiddle.net/mendesjuan/sL7tnfm6/5
$('form[class="ui form"]').on('keydown', 'div[class="ui fluid selection dropdown active visible"]', function (e) {
var keyCode = e.keyCode || e.which;
if (keyCode == 9) {
e.preventDefault();
var y = jQuery.Event('keydown', {which: 13});
$(this).trigger(y);
}
});
The draft code in the question triggers an infinite loop. The key point in the problem is capturing the selected (active) element when the user presses TAB and switches the focus to the next element.
So, it is better to use a function called onblur:
$('form[class="ui form"]').on('blur', '.dropdown', function () {
var y = jQuery.Event('keydown', {which: 13});
$(this).trigger(y);
});

Preventing backspace to go back from the current form

I'm using the below JavaScript function to prevent backspace from going back.
function preventBackspace(e) {
var evt = e || window.event;
if (evt) {
var keyCode = evt.charCode || evt.keyCode;
if (keyCode === 8) {
if (evt.preventDefault) {
evt.preventDefault();
} else {
evt.returnValue = false;
}
}
}
}
I have added onkeydown="preventBackspace();" to all the text boxes.
I have two radio buttons and two textboxes which when checked make the other textbox readonly. When hitting the backspace key it is not going to back page, but I am not able to delete from the editable text box. Please suggest. Thanks!
When the user is currently focused on a textbox, the backspace key does not cause the browser to go back. The backspace in a textbox is used to delete a character - and since you've added preventDefault(), you're stopping that behavior from happening.
If your goal is to prevent the user from accidentally leaving the form before they are finished, you can use window.onbeforeunload to display a warning message that allows the user to cancel navigation:
window.onbeforeunload = function() {
return "Are you sure you want to leave this page? Your current entries" +
" will be lost.";
};

Prevent a button from submitting a form when 'enter' is pressed in a certain location

I have a table with a quick edit function (updates only one field using AJAX), and I wish for 'enter' to submit the change. Trouble is, I have a button on a form on the same page, and every time I press 'enter' the action attached to that button (i.e. submit the form, which I do not want to do) is fired, and I cannot figure out for the life of me how to prevent that.
I've tried the following code, preventing the default on the keyup event (which is probably wrong) and on the button. My understanding though is that you prevent the default of an event, not an object, so I'm really not sure what to do -
/** Capture a key press (while a field within the quick edit row is selected) */
qeRow.keyup(function(e){
e.preventDefault(); // Also tried '$('#change-permissions-button').preventDefault'
if(e.keyCode === 27) { // Cancel on 'escape' (This is working fine)
return inlineEditUserGroup.revert();
} else if(e.keyCode === 13) { // Save the data on 'enter'
return inlineEditUserGroup.save();
}
});
Thanks.
Try listening to the keydown or keypress event.
qeRow.keypress(function(e){
e.preventDefault(); // Also tried '$('#change-permissions-button').preventDefault'
if(e.keyCode === 27) { // Cancel on 'escape' (This is working fine)
return inlineEditUserGroup.revert();
} else if(e.keyCode === 13) { // Save the data on 'enter'
return inlineEditUserGroup.save();
}
});
I guess the keyup-event is triggered 'to late', because it only listens to a key after you pressed in, and than the form is already submitted.

Submit buttons and Enter key issues

I'm trying to prevent form submit if users has focus on any submit button or input type text (as in a filtering datagrid).
I'm considering 2 options
replace submit button with some kind of <p onclick='submitform&parameters'>Add</p>
block the enter key on buttons and some preferred input fields
Is there a better way to do this?
If you add an onKeyPress event to the element in question, you can prevent the default action (form submission) by returning false from the function:
<input id="txt" type="text" onKeyPress="var key = event.keyCode || event.which; if (key == 13) return false;"></input>
Note that the which property of the keyboard event is deprecated, but you'll still want to check for it to support older user agents and/or Internet Exploder (reference).
If you don't want to use inline javascript (which is not recommended), you can instead attach an event. Also, it may be better to use the preventDefault (docs) method of the event object, as well as the stopPropagation method (docs) - the necessity for these methods this is highly dependent on what other events you have attached to the form or the elements:
var preventFormSubmit = function (event) {
var key = event.keyCode || event.which;
if (key != 13)
return;
if (event.stopPropagation) event.stopPropagation();
else event.cancelBubble = true; // deprecated, for older IE
if (event.preventDefault) event.preventDefault();
else event.returnValue = false; // deprecated, for older IE
return false;
};
var target = document.getElementById('txt');
if (typeof target.addEventListener == 'function')
target.addEventListener('keypress', preventFormSubmit, false);
else if (typeof target.attachEvent == 'function')
target.attachEvent('onkeypress', preventFormSubmit);
There are other approaches to use, such as attaching a more complex onSumit handler to the form itself - this may be more appropriate if you're going to be doing further manipulation of the form or data before submitting (or using AJAX to submit the form data).
Solution
input id="txt" type="text" onKeyPress="if (event.which == 13) return false;"></input>
Link
http://stackoverflow.com/questions/1567644/submit-form-problem-enter-key
Question closed

Javascript: How can I block the backspace character?

I don't want my website's user to use backspace to go to the previous page,
but I still want to keep the use of backspace,
just like deleting wrong typing.
How can I do?
Thanks a lot.
As others have mentioned there are methods in which you can monitor for backspace key events and perform different actions.
I recommend against catching the backspace key for a couple of reasons:
1) It's simply irritating and irritated users are likely to not return to your page.
2) Backspace is not the only method of returning to the previous page. There are other key combinations that can accomplish the same thing, as well as the obvious "back button".
Don't do it - but if you must, use onbeforeunload() rather than trapping browser specific key strokes.
Solution: Place the following code toward the end of all your pages that contain forms:
<!-- Block the Backspace and Enter keys in forms, outside of input texts and textareas -->
<script type="text/javascript">
function blockBackspaceAndEnter(e) {
if (!e) { // IE reports window.event instead of the argument
e = window.event;
}
var keycode;
if (document.all) {
// IE
keycode = e.keyCode;
} else {
// Not IE
keycode = e.which;
}
// Enter is only allowed in textareas, and Backspace is only allowed in textarea and input text and password
if ((keycode == 8
&& e.srcElement.type != "text"
&& e.srcElement.type != "textarea"
&& e.srcElement.type != "password")
|| (keycode == 13 && e.srcElement.type != "textarea")) {
e.keyCode = 0;
if (document.all) {
// IE
event.returnValue = false;
} else {
// Non IE
Event.stop(e);
}
}
}
for (var i = 0; i < document.forms.length; i++) {
document.forms[i].onkeydown = blockBackspaceAndEnter;
}
</script>
I have the following comments about what other people answered here before:
Someone said:
"Please don't. Users like
backspace-to-go-back; going back is
one of the most vital browser features
and breaking it is intolerably rude."
My answer to him is:
Yes, usually people DO use the back-button to go back, BUT NOT on pages with FORMS. On the other hand it is really easy for people to accidentally click near or outside an input text or textarea, and then press the back button, so they will lose all their edits, as someone else also noticed:
"Users aren't in a textbox and hit the
backspace, completely losing all the
form information they've just entered.
Wouldn't normally be a problem, but
for us, we're filling out lots of text
on long state forms."
The same undesired behaviour can also be said about the Enter key to submit the form, which usually is only desirable (if ever) for small forms with a few fields, but not for forms with many fields and select boxes and input boxes and textareas, in which most of the time you DO NOT want that the form is submitted when you press Enter.
So this is why I suggest the code above, which applies to all <FORM> tags the function suggested by webster, but without the checks for ALT, which I don't think is useful, and without the checks for CTRL+N and CTRL+R and CTRL+F5, which we don't want to block, because when they are used they are NOT accidental.
Unfortunately, the code above does not work in Firefox when you have DIVs and TABLEs inside your FORM! That is because the keydown event seems to not be propagated to the containing form, and instead the default (UNDESIRED!) behaviour is applied for the Backspace and Enter keys.
I couldn't yet find a solution for this one...
You can use the "onbeforeunload" property on the body tag to prompt the user that he is leaving the page.
You can simply use the following code snippets to block the backspace when the cursor is in texarea, text and password controls.
function onKeyDown()
{
if((event.altKey) || ((event.keyCode == 8) &&
(event.srcElement.type != "text" &&
event.srcElement.type != "textarea" &&
event.srcElement.type != "password")) ||
((event.ctrlKey) && ((event.keyCode == 78) || (event.keyCode == 82)) ) || (event.keyCode == 116) ) {
event.keyCode = 0;
event.returnValue = false;}
}
Call this function from body tag onkeydown event
Filme Noi Cinema has the right answer, but the example code is a bit dated. I just needed this solution so I thought I would post the code I used.
//I use the standard DOM method for accessing the body tag, because the
//non-standard HTML DOM shortcuts are not stable. The correct behavior is
//dynamically attached to the entire body using the onkeypress event, which
//is the most stable event to target cross browser.
document.getElementsByTagName("body")[0].onkeypress = function (event) {
var a = event || window.event, //get event cross browser
b = a.target || a.srcElement; //get source cross browser
//the only thing that matters is the backspace key
if (a.keyCode === 8) {
//if you are a textarea or input type text or password then fail
if (b.nodeName === "textarea" || (b.nodeName === "input" && (b.getAttribute("type") === "text" || b.getAttribute("type") === "password"))) {
return true;
} else {
//backspace is disabled for everything else
return false;
}
}
};
This code needs to be executed before the user starts engaging the page. There are numerous ways to do this:
You can put the above code into any function that is already attached to the onload event.
You can wrap the above code that is bound to the page's onload event.
You can put the above code into a self executing function.
Examples:
//self executing function
(function () {
the solution code here
}());
//wrapper to onload event
document.getElementsByTagName("body")[0].onload = function () {
the solution code here
};
I am adding this code to Pretty Diff if you want to see an example in action.
You should be able to attach a onKeydown/Up/Press listener to your window. In this function, look at the keycode that was pressed, and at the event target. If the keycode is backspace, and the target is NOT an input box or a textarea, prevent the event.
I finally found one that works on all browsers.
It's by Hazem Saleh
His website address is:
http://www.technicaladvices.com/2012/07/16/preventing-backspace-from-navigating-back-in-all-the-browsers/
/*Starts here:*/
document.onkeydown = function (event) {
if (!event) { /* This will happen in IE */
event = window.event;
}
var keyCode = event.keyCode;
if (keyCode == 8 &&
((event.target || event.srcElement).tagName != "TEXTAREA") &&
((event.target || event.srcElement).tagName != "INPUT")) {
if (navigator.userAgent.toLowerCase().indexOf("msie") == -1) {
event.stopPropagation();
} else {
alert("prevented");
event.returnValue = false;
}
return false;
}
};
/*Ends Here*/

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