Javascript [Electronic resources] : The Definitive Guide (4th Edition) نسخه متنی

Availability

JavaScript 1.5; JScript 5.5, ECMAScript v3

Synopsis

number.toExponential(digits)

Arguments

digits

The number of digits that will appear after the decimal point. This
may be a value between 0 and 20, inclusive, and implementations may
optionally support a larger range of values. If this argument is
omitted, as many digits as necessary will be used.

Returns

A string representation of number, in
exponential notation, with one digit before the decimal place and
digits digits after the decimal place. The
fractional part of the number is rounded, or padded with zeros, as
necessary, so that it has the specified length.

Throws

RangeError

If digits is too small or too large.
Values between 0 and 20, inclusive, will not cause a RangeError.
Implementations are allowed to support larger and smaller values as
well.

TypeError

If this method is invoked on an object that is not a Number.

Example

var n = 12345.6789;
n.toExponential(1);     // Returns 1.2e+4
n.toExponential(5);     // Returns 1.23457e+4
n.toExponential(10);    // Returns 1.2345678900e+4
n.toExponential(  );    // Returns 1.23456789e+4

See Also

Number.toFixed( ), Number.toLocaleString( ), Number.toPrecision( ),
Number.toString( )