Javascript: Move caret to last character

Adam Halasz picture Adam Halasz · Jan 17, 2011 · Viewed 19.2k times · Source

I have a textarea and when I click in it I want to move the caret to the last character so Something[caret]

function moveCaret(){
     // Move caret to the last character
}
<textarea onclick="moveCaret();">
     Something
</textarea>

As I know this is somehow possible with the TextRange object, but I don't really know how to use it

EDIT: I would love to see only pure javascript solutions so no libraries please.

Answer

Tim Down picture Tim Down · Jan 17, 2011

The following function will work in all major browsers, for both textareas and text inputs:

function moveCaretToEnd(el) {
    if (typeof el.selectionStart == "number") {
        el.selectionStart = el.selectionEnd = el.value.length;
    } else if (typeof el.createTextRange != "undefined") {
        el.focus();
        var range = el.createTextRange();
        range.collapse(false);
        range.select();
    }
}

However, you really shouldn't do this whenever the user clicks on the textarea, since the user will not be able to move the caret with the mouse. Instead, do it when the textarea receives focus. There is also a problem in Chrome, which can be worked around as follows:

Full example: http://www.jsfiddle.net/ghAB9/3/

HTML:

<textarea id="test">Something</textarea>

Script:

var textarea = document.getElementById("test");
textarea.onfocus = function() {
    moveCaretToEnd(textarea);

    // Work around Chrome's little problem
    window.setTimeout(function() {
        moveCaretToEnd(textarea);
    }, 1);
};