Is parseInt() supposed to work like this?

Question

If I write this script :

alert(parseInt(\"123blahblahblah456\"));

I get the alert with the value 123

Ideally, shouldn\'t th

Answer 1

Yes, cf all the anwers. I'd like to add that this is why checking if certain value can be converted to a number, it's better to use Number or just +.

Number("123blahblahblah456"); //=> NaN
Number("123"); //=> 123
+"97.221" //=> 97.221
// if the conversion result needs to be an int
Math.round(Number("123.4567")); //=> 123

Be aware though that Number in some cases (unexpectely) returns 0.

+null   //=> 0
+"  "   //=> 0
+""     //=> 0
+false  //=> 0
+[]     //=> 0