Name
parseFloat( ): convert a string to a number â ECMAScript v1
Synopsis
parseFloat(s
)
Arguments
-
s
The string to be parsed and converted to a number.
Returns
The parsed number, or NaN
if s
does not begin with a valid
number. In JavaScript 1.0, parseFloat(
)
returns 0 instead of NaN
when s
cannot be parsed as a number.
Description
parseFloat( )
parses and
returns the first number that occurs in
s
. Parsing stops, and the value is
returned, when parseFloat( )
encounters a character in s
that is not a
valid part of the number. If s
does not
begin with a number that parseFloat(
)
can parse, the function returns the not-a-number value
NaN
. Test for this return value
with the isNaN( )
function. If
you want to parse only the integer portion of a number, use parseInt( )
instead of parseFloat( )
.
See Also
isNaN( ), parseInt( )
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