第39页 DATA TYPES

Number Conversions

Number()     //can be used on any data type;
parseInt()    //converting strings to numbers.
parseFloat() //converting strings to numbers.

var num1 = Number(“Hello world!”);  //NaN
var num2 = Number(“”);              //0
var num3 = Number(“000011”);        //11
var num4 = Number(true);            //1
var num5 = Number("-011");        //-11

var num1 = parseInt(“1234blue”);    //1234
var num2 = parseInt(“”);            //NaN
var num3 = parseInt(“0xA”);         //10 - hexadecimal
var num4 = parseInt(22.5);          //22
var num5 = parseInt(“70”);          //70 - decimal
var num6 = parseInt(“0xf”);         //15 - hexadecimal

var num = parseInt(“0xAF”, 16);       //175
var num1 = parseInt(”AF”, 16);        //175
var num2 = parseInt(”AF”);            //NaN

var num111 = parseInt("70",9)     // 63

var num1 = parseFloat(“1234blue”);    //1234 - integer
var num2 = parseFloat(“0xA”);         //0
var num3 = parseFloat(“22.5”);        //22.5
var num4 = parseFloat(“22.34.5”);     //22.34
var num5 = parseFloat(“0908.5”);      //908.5
var num6 = parseFloat(“3.125e7”);     //31250000