I'm building a terminal emulation and running into an issue with capturing backspace in Firefox. I'm able to nab the first backspace and remove the last character on the input at the prompt, but it won't persist and remove more than one character.
Actual website: /
Replication here: /
JavaScript code
function handleKeys(e){
var evt = e || window.event;
var key = evt.charCode || evt.keyCode;
if(evt.type == "keydown")
{
curr_key = key;
if(key == 8)
{
evt.preventDefault();
if(0 < $('body').text().length)
$('body').text($('body').text().slice(0,-1));
}
}
else if(evt.type == "keypress")
{
if(97 <= key && key <= 122)
{
if(curr_key != key)
$('body').append(String.fromCharCode(key));
}
else
$('body').append(String.fromCharCode(key));
}
}
$(function(){
$('html').live({
keydown:function(e){
handleKeys(e);
},
keypress:function(e){
handleKeys(e);
}
})
})
I'm building a terminal emulation and running into an issue with capturing backspace in Firefox. I'm able to nab the first backspace and remove the last character on the input at the prompt, but it won't persist and remove more than one character.
Actual website: http://term.qt.io/
Replication here: http://jsfiddle/BgtsE/1/
JavaScript code
function handleKeys(e){
var evt = e || window.event;
var key = evt.charCode || evt.keyCode;
if(evt.type == "keydown")
{
curr_key = key;
if(key == 8)
{
evt.preventDefault();
if(0 < $('body').text().length)
$('body').text($('body').text().slice(0,-1));
}
}
else if(evt.type == "keypress")
{
if(97 <= key && key <= 122)
{
if(curr_key != key)
$('body').append(String.fromCharCode(key));
}
else
$('body').append(String.fromCharCode(key));
}
}
$(function(){
$('html').live({
keydown:function(e){
handleKeys(e);
},
keypress:function(e){
handleKeys(e);
}
})
})
-
FYI,
live()is deprecated as of jQuery 1.7. You should usebind()oron(). – Barmar Commented Dec 27, 2012 at 6:16 - Your fiddle works for me. Whether backspace auto-repeats may depend on the OS or browser. I'm using OS X Snow Leopard and Chrome 24. – Barmar Commented Dec 27, 2012 at 6:19
- 1 Using Firefox on Windows 17.0.1 some bug in slice. I will post more detail in the "answer" but it seems like some sort of bug – HMR Commented Dec 27, 2012 at 6:33
- @Barmar: Yeah, it's a Firefox-specific bug. – Zack Zatkin-Gold Commented Dec 27, 2012 at 6:38
-
Workaround is to implement your own auto-repeat. keydown handler calls
setInterval()to repeat the action periodically, keyup handler cancels it. – Barmar Commented Dec 27, 2012 at 6:42
4 Answers
Reset to default 5Try this: http://jsfiddle/NBZG8/1/
You'll need to handle backspace in both keydown and keypress to support Chrome and Firefox
function handleKeys(e){
var evt = e || window.event;
var key = evt.charCode || evt.keyCode;
if (evt.type == "keydown") {
curr_key = key;
if(key == 8 && !$.browser.mozilla) {
backspaceHandler(evt);
}
} else if (evt.type == "keypress") {
if (key == 8) {
backspaceHandler(evt);
} else if (97 <= key && key <= 122) {
if(curr_key != key) {
$('body').append(String.fromCharCode(key));
}
} else {
$('body').append(String.fromCharCode(key));
}
}
}
function backspaceHandler(evt) {
evt.preventDefault();
if(0 < $('body').text().length) {
$('body').text($('body').text().slice(0,-1));
}
};
$(function(){
$('html').live({
keydown : handleKeys,
keypress : handleKeys
})
})
In firefox Windows 17.0.1 any value returned by $("selector").text() has an added new line character appended to the end. So the substring didn't work for me:
<html>
<head>
<title>test</title>
<script src="jquery.js"></script>
<script>
$("document").ready(function(){
console.log("body text seems to have a new line character");
console.log(($('body').text()[5]=="\n"));
});
function handleKeys(e){
var evt = e || window.event;
var key = evt.charCode || evt.keyCode;
if(evt.type == "keydown")
{
curr_key = key;
if(key == 8)
{
evt.preventDefault();
if(0 < $('body').text().length)
// next line works, you might trim the \n if it's there at the end
//$('body').text($('body').text().slice(0,-2));
// this one didn't work for me
$('body').text($('body').text().substring(0,$('body').text().length-1));
}
}
else if(evt.type == "keypress")
{
if(97 <= key && key <= 122)
{
if(curr_key != key)
$('body').append(String.fromCharCode(key));
}
else
$('body').append(String.fromCharCode(key));
}
}
$(function(){
$('html').live({
keydown:function(e){
handleKeys(e);
},
keypress:function(e){
handleKeys(e);
}
})
})
</script>
</head>
<body>12345</body>
</html>
I had the same issue with keypress on mozilla.
Thanks to this subject it solves my problem so I'll post my code if anyone try to do the same thing as me.
In my exemple I try to auto space when the user type two numbers, and it didn't work in Firefox so that's my code :
$(function() {
$('#field1, #field2').on('keypress',function(event) {
event = event || window.event;
var charCode = event.keyCode || event.which,
lgstring = $(this).val().length,
trimstring;
if(charCode === 8) {
event.returnValue = false;
if(event.preventDefault)
event.preventDefault();
if(0 < $(this).val().length) {
$(this).val($(this).val().slice(0,-1));
}
}
else if(((charCode > 31) && (charCode < 48 || charCode > 57)) || lgstring >= 14) {
event.returnValue = false;
if(event.preventDefault)
event.preventDefault();
}
else {
trimstring = $(this).val().replace(/ /g,"");
if((lgstring !== 0) && (trimstring.length % 2) === 0 ) {
$(this).val($(this).val() + ' ');
}
}
});
});
I noticed that Mozilla handle the backspace as a keypress where Chrome don't.
Sorry for my English I'm French
$('#id').keypress(function(e) {
if(e.charCode > 0 || e.keyCode === 8){
if(e.keyCode === 8){
return true;
}else if((e.charCode !== 0) && ((e.charCode > 57 && e.charCode < 65)){
return false;
}
}else if((e.keyCode !== 0) && ((e.keyCode > 57 && e.keyCode < 65)){
return false;
}
});