JavaScript Learning Notes (iv) Number digit type _ basics

ToFixed () method specifies the number of decimal places
The Toexponential () method represents the number with scientific notation, and the parameter specifies the number of decimal places.
The Toprecision () method automatically judges the call to the tofixed () or toexponential () method, and the parameter specifies the number of digits for all numbers

Copy Code code as follows:

var num = 99;
Alert (toFixed (2)); 99.00
Alert (toexponential (1)); 9.0e+1
Alert (toprecision (1)); 9.0e+1
Alert (toprecision (2)); 99
Alert (Toprecision (3)); 99.0