Does anybody know how to move the keyboard caret in a textbox to a particular position?
For example, if a text-box (e.g. input element, not text-area) has 50 characters in it and I want to position the caret before character 20, how would I go about it?
This is in differentiation from this question: jQuery Set Cursor Position in Text Area , which requires jQuery.
This question is related to
javascript
textbox
input
Excerpted from Josh Stodola's Setting keyboard caret Position in a Textbox or TextArea with Javascript
A generic function that will allow you to insert the caret at any position of a textbox or textarea that you wish:
function setCaretPosition(elemId, caretPos) {
var elem = document.getElementById(elemId);
if(elem != null) {
if(elem.createTextRange) {
var range = elem.createTextRange();
range.move('character', caretPos);
range.select();
}
else {
if(elem.selectionStart) {
elem.focus();
elem.setSelectionRange(caretPos, caretPos);
}
else
elem.focus();
}
}
}
The first expected parameter is the ID of the element you wish to insert the keyboard caret on. If the element is unable to be found, nothing will happen (obviously). The second parameter is the caret positon index. Zero will put the keyboard caret at the beginning. If you pass a number larger than the number of characters in the elements value, it will put the keyboard caret at the end.
Tested on IE6 and up, Firefox 2, Opera 8, Netscape 9, SeaMonkey, and Safari. Unfortunately on Safari it does not work in combination with the onfocus event).
An example of using the above function to force the keyboard caret to jump to the end of all textareas on the page when they receive focus:
function addLoadEvent(func) {
if(typeof window.onload != 'function') {
window.onload = func;
}
else {
if(func) {
var oldLoad = window.onload;
window.onload = function() {
if(oldLoad)
oldLoad();
func();
}
}
}
}
// The setCaretPosition function belongs right here!
function setTextAreasOnFocus() {
/***
* This function will force the keyboard caret to be positioned
* at the end of all textareas when they receive focus.
*/
var textAreas = document.getElementsByTagName('textarea');
for(var i = 0; i < textAreas.length; i++) {
textAreas[i].onfocus = function() {
setCaretPosition(this.id, this.value.length);
}
}
textAreas = null;
}
addLoadEvent(setTextAreasOnFocus);
HTMLInputElement.setSelectionRange( selectionStart, selectionEnd );
// References
var e = document.getElementById( "helloworldinput" );
// Move caret to beginning on focus
e.addEventListener( "focus", function( event )
{
// References
var e = event.target;
// Action
e.setSelectionRange( 0, 0 ); // Doesn’t work for focus event
window.setTimeout( function()
{
e.setSelectionRange( 0, 0 ); // Works
//e.setSelectionRange( 1, 1 ); // Move caret to second position
//e.setSelectionRange( 1, 2 ); // Select second character
}, 0 );
}, false );
Browser compatibility (only for types: text, search, url, tel and password): https://developer.mozilla.org/en-US/docs/Web/API/HTMLInputElement/setSelectionRange#Specifications
I would fix the conditions like below:
function setCaretPosition(elemId, caretPos)
{
var elem = document.getElementById(elemId);
if (elem)
{
if (typeof elem.createTextRange != 'undefined')
{
var range = elem.createTextRange();
range.move('character', caretPos);
range.select();
}
else
{
if (typeof elem.selectionStart != 'undefined')
elem.selectionStart = caretPos;
elem.focus();
}
}
}
The link in the answer is broken, this one should work (all credits go to blog.vishalon.net):
http://snipplr.com/view/5144/getset-cursor-in-html-textarea/
In case the code gets lost again, here are the two main functions:
function doGetCaretPosition(ctrl)
{
var CaretPos = 0;
if (ctrl.selectionStart || ctrl.selectionStart == 0)
{// Standard.
CaretPos = ctrl.selectionStart;
}
else if (document.selection)
{// Legacy IE
ctrl.focus ();
var Sel = document.selection.createRange ();
Sel.moveStart ('character', -ctrl.value.length);
CaretPos = Sel.text.length;
}
return (CaretPos);
}
function setCaretPosition(ctrl,pos)
{
if (ctrl.setSelectionRange)
{
ctrl.focus();
ctrl.setSelectionRange(pos,pos);
}
else if (ctrl.createTextRange)
{
var range = ctrl.createTextRange();
range.collapse(true);
range.moveEnd('character', pos);
range.moveStart('character', pos);
range.select();
}
}
If you need to focus some textbox and your only problem is that the entire text gets highlighted whereas you want the caret to be at the end, then in that specific case, you can use this trick of setting the textbox value to itself after focus:
$("#myinputfield").focus().val($("#myinputfield").val());
I've adjusted the answer of kd7 a little bit because elem.selectionStart will evaluate to false when the selectionStart is incidentally 0.
function setCaretPosition(elem, caretPos) {
var range;
if (elem.createTextRange) {
range = elem.createTextRange();
range.move('character', caretPos);
range.select();
} else {
elem.focus();
if (elem.selectionStart !== undefined) {
elem.setSelectionRange(caretPos, caretPos);
}
}
}
I would fix the conditions like below:
function setCaretPosition(elemId, caretPos)
{
var elem = document.getElementById(elemId);
if (elem)
{
if (typeof elem.createTextRange != 'undefined')
{
var range = elem.createTextRange();
range.move('character', caretPos);
range.select();
}
else
{
if (typeof elem.selectionStart != 'undefined')
elem.selectionStart = caretPos;
elem.focus();
}
}
}
<!DOCTYPE html>
<html>
<head>
<title>set caret position</title>
<script type="application/javascript">
//<![CDATA[
window.onload = function ()
{
setCaret(document.getElementById('input1'), 13, 13)
}
function setCaret(el, st, end)
{
if (el.setSelectionRange)
{
el.focus();
el.setSelectionRange(st, end);
}
else
{
if (el.createTextRange)
{
range = el.createTextRange();
range.collapse(true);
range.moveEnd('character', end);
range.moveStart('character', st);
range.select();
}
}
}
//]]>
</script>
</head>
<body>
<textarea id="input1" name="input1" rows="10" cols="30">Happy kittens dancing</textarea>
<p> </p>
</body>
</html>
The link in the answer is broken, this one should work (all credits go to blog.vishalon.net):
http://snipplr.com/view/5144/getset-cursor-in-html-textarea/
In case the code gets lost again, here are the two main functions:
function doGetCaretPosition(ctrl)
{
var CaretPos = 0;
if (ctrl.selectionStart || ctrl.selectionStart == 0)
{// Standard.
CaretPos = ctrl.selectionStart;
}
else if (document.selection)
{// Legacy IE
ctrl.focus ();
var Sel = document.selection.createRange ();
Sel.moveStart ('character', -ctrl.value.length);
CaretPos = Sel.text.length;
}
return (CaretPos);
}
function setCaretPosition(ctrl,pos)
{
if (ctrl.setSelectionRange)
{
ctrl.focus();
ctrl.setSelectionRange(pos,pos);
}
else if (ctrl.createTextRange)
{
var range = ctrl.createTextRange();
range.collapse(true);
range.moveEnd('character', pos);
range.moveStart('character', pos);
range.select();
}
}
If you need to focus some textbox and your only problem is that the entire text gets highlighted whereas you want the caret to be at the end, then in that specific case, you can use this trick of setting the textbox value to itself after focus:
$("#myinputfield").focus().val($("#myinputfield").val());
I found an easy way to fix this issue, tested in IE and Chrome:
function setCaret(elemId, caret)
{
var elem = document.getElementById(elemId);
elem.setSelectionRange(caret, caret);
}
Pass text box id and caret position to this function.
function SetCaretEnd(tID) {
tID += "";
if (!tID.startsWith("#")) { tID = "#" + tID; }
$(tID).focus();
var t = $(tID).val();
if (t.length == 0) { return; }
$(tID).val("");
$(tID).val(t);
$(tID).scrollTop($(tID)[0].scrollHeight); }
HTMLInputElement.setSelectionRange( selectionStart, selectionEnd );
// References
var e = document.getElementById( "helloworldinput" );
// Move caret to beginning on focus
e.addEventListener( "focus", function( event )
{
// References
var e = event.target;
// Action
e.setSelectionRange( 0, 0 ); // Doesn’t work for focus event
window.setTimeout( function()
{
e.setSelectionRange( 0, 0 ); // Works
//e.setSelectionRange( 1, 1 ); // Move caret to second position
//e.setSelectionRange( 1, 2 ); // Select second character
}, 0 );
}, false );
Browser compatibility (only for types: text, search, url, tel and password): https://developer.mozilla.org/en-US/docs/Web/API/HTMLInputElement/setSelectionRange#Specifications
I've adjusted the answer of kd7 a little bit because elem.selectionStart will evaluate to false when the selectionStart is incidentally 0.
function setCaretPosition(elem, caretPos) {
var range;
if (elem.createTextRange) {
range = elem.createTextRange();
range.move('character', caretPos);
range.select();
} else {
elem.focus();
if (elem.selectionStart !== undefined) {
elem.setSelectionRange(caretPos, caretPos);
}
}
}
Since I actually really needed this solution, and the typical baseline solution (focus the input - then set the value equal to itself) doesn't work cross-browser, I spent some time tweaking and editing everything to get it working. Building upon @kd7's code here's what I've come up with.
Enjoy! Works in IE6+, Firefox, Chrome, Safari, Opera
Cross-browser caret positioning technique (example: moving the cursor to the END)
// ** USEAGE ** (returns a boolean true/false if it worked or not)
// Parameters ( Id_of_element, caretPosition_you_want)
setCaretPosition('IDHERE', 10); // example
The meat and potatoes is basically @kd7's setCaretPosition, with the biggest tweak being if (el.selectionStart || el.selectionStart === 0), in firefox the selectionStart is starting at 0, which in boolean of course is turning to False, so it was breaking there.
In chrome the biggest issue was that just giving it .focus() wasn't enough (it kept selecting ALL of the text!) Hence, we set the value of itself, to itself el.value = el.value; before calling our function, and now it has a grasp & position with the input to use selectionStart.
function setCaretPosition(elemId, caretPos) {
var el = document.getElementById(elemId);
el.value = el.value;
// ^ this is used to not only get "focus", but
// to make sure we don't have it everything -selected-
// (it causes an issue in chrome, and having it doesn't hurt any other browser)
if (el !== null) {
if (el.createTextRange) {
var range = el.createTextRange();
range.move('character', caretPos);
range.select();
return true;
}
else {
// (el.selectionStart === 0 added for Firefox bug)
if (el.selectionStart || el.selectionStart === 0) {
el.focus();
el.setSelectionRange(caretPos, caretPos);
return true;
}
else { // fail city, fortunately this never happens (as far as I've tested) :)
el.focus();
return false;
}
}
}
}
function SetCaretEnd(tID) {
tID += "";
if (!tID.startsWith("#")) { tID = "#" + tID; }
$(tID).focus();
var t = $(tID).val();
if (t.length == 0) { return; }
$(tID).val("");
$(tID).val(t);
$(tID).scrollTop($(tID)[0].scrollHeight); }
Since I actually really needed this solution, and the typical baseline solution (focus the input - then set the value equal to itself) doesn't work cross-browser, I spent some time tweaking and editing everything to get it working. Building upon @kd7's code here's what I've come up with.
Enjoy! Works in IE6+, Firefox, Chrome, Safari, Opera
Cross-browser caret positioning technique (example: moving the cursor to the END)
// ** USEAGE ** (returns a boolean true/false if it worked or not)
// Parameters ( Id_of_element, caretPosition_you_want)
setCaretPosition('IDHERE', 10); // example
The meat and potatoes is basically @kd7's setCaretPosition, with the biggest tweak being if (el.selectionStart || el.selectionStart === 0), in firefox the selectionStart is starting at 0, which in boolean of course is turning to False, so it was breaking there.
In chrome the biggest issue was that just giving it .focus() wasn't enough (it kept selecting ALL of the text!) Hence, we set the value of itself, to itself el.value = el.value; before calling our function, and now it has a grasp & position with the input to use selectionStart.
function setCaretPosition(elemId, caretPos) {
var el = document.getElementById(elemId);
el.value = el.value;
// ^ this is used to not only get "focus", but
// to make sure we don't have it everything -selected-
// (it causes an issue in chrome, and having it doesn't hurt any other browser)
if (el !== null) {
if (el.createTextRange) {
var range = el.createTextRange();
range.move('character', caretPos);
range.select();
return true;
}
else {
// (el.selectionStart === 0 added for Firefox bug)
if (el.selectionStart || el.selectionStart === 0) {
el.focus();
el.setSelectionRange(caretPos, caretPos);
return true;
}
else { // fail city, fortunately this never happens (as far as I've tested) :)
el.focus();
return false;
}
}
}
}
Source: Stackoverflow.com