Data type conversion
Into a string
String (value) transformation function
Can any type of value this function transformation into a string
- If the values are toString () method is to use this method (calling toString no parameters, the default decimal)
- If the value is null and undefined undefined and null is returned
toString () method ---- index.toString (parameter (this parameter is a number converted to a string of hexadecimal number))
In addition to null and undefined values do not have this method, the value of other types have this method
Into digital
Number () function (default decimal )
- It can be transformed into any type
- String type:
- If 0 is the empty string
- Recognition - + number (other symbols returns NaN)
- null Type: return 0
- undefined type: returns undefined
- Value Type: unchanged
- boolean type: true: 1 false: 0
- Complex and unreasonable
The following two special strings to digital conversion
parseInt (parameter 1, parameter 2 (preferably set to 10 decimal)) (value Type more care Meets) function
Ignore spaces in front of the string, only to find alphanumeric characters and the minus / plus
An empty string will return NaN
Encountered non-numeric characters will terminate
parseFloat () function can only be resolved resolved decimal decimal
Higher-order functions
Function can be passed as parameters