the most darndest thing! the following code prints out 'llo' instead of the expected 'wo'. i get such surprising results for a few other numbers. what am i missing here?
alert('helloworld'.substring(5, 2));
6 Answers
You're confusing substring() and substr(): substring() expects two indices and not offset and length. In your case, the indices are 5 and 2, ie characters 2..4 will be returned as the higher index is excluded.
Check the substring syntax:
substring(from, to)
from Required. The index where to start the extraction. First character is at index 0
to Optional. The index where to stop the extraction. If omitted, it extracts the rest of the string
I'll grant you it's a bit odd. Didn't know that myself.
What you want to do is
alert('helloworld'.substring(5, 7));
alert('helloworld'.substring(5, 2));
The code above is wrong because the first value is the start point to the end point.E.g move from char 5 which is o and go to char 2 which is the l so will get llo So you have told it to go backwards.
What yuou want is
alert('helloworld'.substring(5, 7));
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