jQuery Set Cursor Position in Text Area

Question

How do you set the cursor position in a text field using jQuery? I\'ve got a text field with content, and I want the users cursor to be positioned at a certain offset when

Answer 1

I do realize that this is a very old post, but I thought that I should offer perhaps a simpler solution to update it using only jQuery.

function getTextCursorPosition(ele) {   
    return ele.prop("selectionStart");
}

function setTextCursorPosition(ele,pos) {
    ele.prop("selectionStart", pos + 1);
    ele.prop("selectionEnd", pos + 1);
}

function insertNewLine(text,cursorPos) {
    var firstSlice = text.slice(0,cursorPos);
    var secondSlice = text.slice(cursorPos);

    var new_text = [firstSlice,"\n",secondSlice].join('');

    return new_text;
}

Usage for using ctrl-enter to add a new line (like in Facebook):

$('textarea').on('keypress',function(e){
    if (e.keyCode == 13 && !e.ctrlKey) {
        e.preventDefault();
        //do something special here with just pressing Enter
    }else if (e.ctrlKey){
        //If the ctrl key was pressed with the Enter key,
        //then enter a new line break into the text
        var cursorPos = getTextCursorPosition($(this));                

        $(this).val(insertNewLine($(this).val(), cursorPos));
        setTextCursorPosition($(this), cursorPos);
    }
});

I am open to critique. Thank you.

UPDATE: This solution does not allow normal copy and paste functionality to work (i.e. ctrl-c, ctrl-v), so I will have to edit this in the future to make sure that part works again. If you have an idea how to do that, please comment here, and I will be happy to test it out. Thanks.

Answer 2

You can directly change the prototype if setSelectionRange does not exist.

(function() {
    if (!HTMLInputElement.prototype.setSelectionRange) {
        HTMLInputElement.prototype.setSelectionRange = function(start, end) {
            if (this.createTextRange) {
                var range = this.createTextRange();
                this.collapse(true);
                this.moveEnd('character', end);
                this.moveStart('character', start);
                this.select();
            }
        }
    }
})();
document.getElementById("input_tag").setSelectionRange(6, 7);

jsFiddle link

Answer 3

Just remember to return false right after the function call if you're using the arrow keys since Chrome fricks the frack up otherwise.

{
    document.getElementById('moveto3').setSelectionRange(3,3);
    return false;
}

Answer 4

As for me here the most easily way to add text(Tab -> \t) in textarea by cursor position and save the focus on cursor:

$('#text').keyup(function () {
    var cursor = $('#text').prop('selectionStart');
    //if cursot is first in textarea
    if (cursor == 0) {
        //i will add tab in line
        $('#text').val('\t' + $('#text').val());
        //here we set the cursor position
        $('#text').prop('selectionEnd', 1);
    } else {
        var value = $('#text').val();
        //save the value before cursor current position
        var valToCur = value.substring(0, cursor);
        //save the value after cursor current position
        var valAfter = value.substring(cursor, value.length);
        //save the new value with added tab in text
        $('#text').val(valToCur + '\t' + valAfter);
        //set focus of cursot after insert text (1 = because I add only one symbol)
        $('#text').prop('selectionEnd', cursor + 1);
    }
});