Question

I need to replace all the matches of a regular expression till the caret position in a textarea using Javascript.
For example, if the text in the textarea is: “6 students carry 2 books to 5 classes” and the cursor
is placed on books and the regular expression is /\d/, the numbers 6 and 2 should be replaced by, say, 4.
I know the replace function and I know how to get the caret position, but how do I solve this problem?
Thanks for any help in advance!

Answer 1

textareaClicked = function(e){
    var pos = e.target.selectionStart;
    var beforeSelection = e.target.innerHTML.slice(0,pos);
    var afterSelection = e.target.innerHTML.slice(pos);
    var newHTML = beforeSelection.replace(/\d/g,4) + afterSelection;
    e.target.innerHTML = newHTML;
    e.target.setSelectionRange(pos,pos);
};

document.getElementById('foo').onclick=textareaClicked;

see it in action in this jsfiddle.