js中的一些类型转换

1.转换成字符串
var num = 10;
num.toString(2) = “1010”
num.toString(8) = "12"
num.toString(10) = num.toString() = "10"
2.转换成数字
parseInt("1234blue") = 1234
parseInt("blue") = NaN
parseInt("0xA") = 10     //0x开头表示16进制
parseInt("010") = parseInt("010",8) = 8     //0开头默认为8进制
parseInt("22.5") = 22
parseInt("AF"，16) = 175    //按照十六进制转换，输出10进制结果
parseFloat("22.34.5") = 22.34    parseInt("22.34.5") = 22
parseFloat("0908") = 908
3.强制类型转换
Boolean（value）                        Number(value)                   String(value)                    
Boolean("") = false                     Number("3.4.5") = NaN           String(null) = "null"
Boolean("false") = true                 Number(false) = 0               var obj = null;
Boolean(100) = true                     Number(true) = 1                var s2 = obj.toString() //error
Boolean(0) = false                      Number(undefined) = NaN        
Boolean(null) = false                                                  
Boolean(new Object()) = true