Get cursor position (in characters) within a text Input field
How can I get the caret position from within an input field?
I have found a few bits and pieces via Google, but nothing bullet proof.
Basical开发者_StackOverflow中文版ly something like a jQuery plugin would be ideal, so I could simply do
$("#myinput").caretPosition()
Easier update:
Use field.selectionStart example in this answer.
Thanks to @commonSenseCode for pointing this out.
Old answer:
Found this solution. Not jquery based but there is no problem to integrate it to jquery:
/*
** Returns the caret (cursor) position of the specified text field (oField).
** Return value range is 0-oField.value.length.
*/
function doGetCaretPosition (oField) {
// Initialize
var iCaretPos = 0;
// IE Support
if (document.selection) {
// Set focus on the element
oField.focus();
// To get cursor position, get empty selection range
var oSel = document.selection.createRange();
// Move selection start to 0 position
oSel.moveStart('character', -oField.value.length);
// The caret position is selection length
iCaretPos = oSel.text.length;
}
// Firefox support
else if (oField.selectionStart || oField.selectionStart == '0')
iCaretPos = oField.selectionDirection=='backward' ? oField.selectionStart : oField.selectionEnd;
// Return results
return iCaretPos;
}
Use selectionStart. It is compatible with all major browsers.
document.getElementById('foobar').addEventListener('keyup', e => {
console.log('Caret at: ', e.target.selectionStart)
})<input id="foobar" />This works only when no type is defined or type="text" or type="textarea" on the input.
I've wrapped the functionality in bezmax's answer into jQuery if anyone wants to use it.
(function($) {
$.fn.getCursorPosition = function() {
var input = this.get(0);
if (!input) return; // No (input) element found
if ('selectionStart' in input) {
// Standard-compliant browsers
return input.selectionStart;
} else if (document.selection) {
// IE
input.focus();
var sel = document.selection.createRange();
var selLen = document.selection.createRange().text.length;
sel.moveStart('character', -input.value.length);
return sel.text.length - selLen;
}
}
})(jQuery);
Got a very simple solution. Try the following code with verified result-
<html>
<head>
<script>
function f1(el) {
var val = el.value;
alert(val.slice(0, el.selectionStart).length);
}
</script>
</head>
<body>
<input type=text id=t1 value=abcd>
<button onclick="f1(document.getElementById('t1'))">check position</button>
</body>
</html>
I'm giving you the fiddle_demo
There is now a nice plugin for this: The Caret Plugin
Then you can get the position using $("#myTextBox").caret() or set it via $("#myTextBox").caret(position)
(function($) {
$.fn.getCursorPosition = function() {
var input = this.get(0);
if (!input) return; // No (input) element found
if (document.selection) {
// IE
input.focus();
}
return 'selectionStart' in input ? input.selectionStart:'' || Math.abs(document.selection.createRange().moveStart('character', -input.value.length));
}
})(jQuery);
There are a few good answers posted here, but I think you can simplify your code and skip the check for inputElement.selectionStart support: it is not supported only on IE8 and earlier (see documentation) which represents less than 1% of the current browser usage.
var input = document.getElementById('myinput'); // or $('#myinput')[0]
var caretPos = input.selectionStart;
// and if you want to know if there is a selection or not inside your input:
if (input.selectionStart != input.selectionEnd)
{
var selectionValue =
input.value.substring(input.selectionStart, input.selectionEnd);
}
Perhaps you need a selected range in addition to cursor position. Here is a simple function, you don't even need jQuery:
function caretPosition(input) {
var start = input[0].selectionStart,
end = input[0].selectionEnd,
diff = end - start;
if (start >= 0 && start == end) {
// do cursor position actions, example:
console.log('Cursor Position: ' + start);
} else if (start >= 0) {
// do ranged select actions, example:
console.log('Cursor Position: ' + start + ' to ' + end + ' (' + diff + ' selected chars)');
}
}
Let's say you wanna call it on an input whenever it changes or mouse moves cursor position (in this case we are using jQuery .on()). For performance reasons, it may be a good idea to add setTimeout() or something like Underscores _debounce() if events are pouring in:
$('input[type="text"]').on('keyup mouseup mouseleave', function() {
caretPosition($(this));
});
Here is a fiddle if you wanna try it out: https://jsfiddle.net/Dhaupin/91189tq7/
const inpT = document.getElementById("text-box");
const inpC = document.getElementById("text-box-content");
// swch gets inputs .
var swch;
// swch if corsur is active in inputs defaulte is false .
var isSelect = false;
var crnselect;
// on focus
function setSwitch(e) {
swch = e;
isSelect = true;
console.log("set Switch: " + isSelect);
}
// on click ev
function setEmoji() {
if (isSelect) {
console.log("emoji added :)");
swch.value += ":)";
swch.setSelectionRange(2,2 );
isSelect = true;
}
}
// on not selected on input .
function onout() {
// الافنت اون كي اب
crnselect = inpC.selectionStart;
// return input select not active after 200 ms .
var len = swch.value.length;
setTimeout(() => {
(len == swch.value.length)? isSelect = false:isSelect = true;
}, 200);
}<h1> Try it !</h1>
<input type="text" onfocus = "setSwitch(this)" onfocusout = "onout()" id="text-box" size="20" value="title">
<input type="text" onfocus = "setSwitch(this)" onfocusout = "onout()" id="text-box-content" size="20" value="content">
<button onclick="setEmoji()">emogi :) </button>The solution is .selectionStart:
var input = document.getElementById('yourINPUTid');
input.selectionEnd = input.selectionStart = yourDESIREDposition;
input.focus();
If .selectionEnd is not assiged, some text (S-->E) will be selected.
.focus() is required when the focus is lost; when you trigger your code (onClick).
I only tested this in Chrome.
If you want more complicated solutions, you have to read the other answers.
加载中,请稍侯......
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