May 2008
Intermediate to advanced
172 pages
4h 54m
English
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parseInt
parseInt is a function that converts a string
into an integer. It stops when it sees a nondigit, so parseInt("16") and parseInt("16
tons") produce the same result. It would be nice if the function
somehow informed us about the extra text, but it doesn't.
If the first character of the string is 0, then the string is evaluated in base 8
instead of base 10. In base 8, 8 and 9 are not digits, so parseInt("08") and parseInt("09")
produce 0 as their result. This error causes problems in programs that parse dates
and times. Fortunately, parseInt can take a radix
parameter, so that parseInt("08", 10) produces 8.
I recommend that you always provide the radix parameter.