I am writing a javascript function that needs to check first whether the user has highlighted / selected some text on the page. I read online that this should work:

if ( typeof window.getSelection() != "undefined" ) {
    var x = window.getSelection().toString();
}
else {
    //nothing is selected, so use default value
    var x = "default value";
}

But that did not work because even when nothing is selected, window.getSelection() returns an object.

if ( typeof window.getSelection().toString() !== "" ) {
    var x = window.getSelection().toString();
}
else {
    //nothing is selected, so use default value
    var x = "default value";
}

But even though window.getSelection().toString() returns an empty string, it still uses that empty string rather than the default value.

Finally, if ( window.getSelection() ) did not work either.

How can I know whether something is selected?

I am writing a javascript function that needs to check first whether the user has highlighted / selected some text on the page. I read online that this should work:

if ( typeof window.getSelection() != "undefined" ) {
    var x = window.getSelection().toString();
}
else {
    //nothing is selected, so use default value
    var x = "default value";
}

But that did not work because even when nothing is selected, window.getSelection() returns an object.

if ( typeof window.getSelection().toString() !== "" ) {
    var x = window.getSelection().toString();
}
else {
    //nothing is selected, so use default value
    var x = "default value";
}

But even though window.getSelection().toString() returns an empty string, it still uses that empty string rather than the default value.

Finally, if ( window.getSelection() ) did not work either.

How can I know whether something is selected?

• javascript

1 Answer 1

This will work: http://jsfiddle/tknkh9xa/1/

(window.getSelection().toString() != "")

Your problem was that you were checking the typeof on the result of the toString()... which would not be an empty string (it would be "string").

Also, since an empty string is a falsy value, you could do just
if(window.getSelection().toString())