1.JavaScript converter comprising: a cast and the basic conversion
Such as:
var str = 'A',num=10，nu=null，t=true,und=undefined,x;
// Note: The definition x has not been initialized; default is undefined
Cast:
Number (str); // output: NaN because str is not a number
Number (undefined); // output: NaN because str is not a number
Number (null); // Output 0
Number (true); // Output 1
Number (false); // Output 0
String (num); // Output: "10" string
String (null); // Output: "null" strings
String (undefined); // Output: "undefined" string
String (true); // Output: "true" string
Boolean(0);// false
Boolean("")；空 false
Boolean（null）；false
Boolean（undefined）；false
Non-mandatory conversion :( binary, decimal, octal, hexadecimal conversion)
parseInt (str, 16); // second parameter specifies the original binary string; 10 10 decimal final output format;
parseFloat (str); // NaN non-numeric
num.toString (2); // Output: binary string "1010";
num.toString (16); // outputs a hexadecimal
nu.toString (); // error; as null and undefined values are not converted
t.toString (); // Returns string "true"
Mandatory and fundamental differences conversion methods:
1. The entire cast is substantially converted value of the conversion is the conversion and the beginning of one part.
2. generally do not know in the end is what type of variable type; you can use casts
Such as: String (null), Boolean (null); as cast can be converted to any type of variable