Conversion of JS type to string and Boolean type

In the previous article, we talked about how to turn a numeric type, and today summarizes the methods for turning strings and Boolean types:

The main methods of the string transfer are:

ToString ();

String ();

The specific usage is shown in the following table:

Method	Example	return value	Description
ToString (): Undefined and null do not have the ToString () method	[' 1 ', ' 2 ', ' 3 '].tostring ()	The	Converts the element of an Array to a string. The resulting strings are separated by commas and joined together.
	True.tostring ()	"True"	Returns "true" if the Boolean value is true. Otherwise, return "false".
	var num = 111; Console.log (Num.tostring ());	"111"	Numeric type to String type
String ()	string () converts null and undefined to a string, but cannot be converted to a string. String (NULL), which returns "null". String (undefined), which returns "undefined".

The main types of turn Boolean methods are:

Boolean ():

The specific usage is shown in the following table:

Method	Example	return value	Description
Boolean (): Convert any type of value to a Boolean value	Boolean (False)	False	False, "", 0, NaN, null, undefined, and any other value will be converted to true.
	Boolean ("")	False
	Boolean (0)	False
	Boolean (NaN)	False
	Boolean (undefined)	False
	Boolean ("false")	True
The string type "false" turns to a Boolean type of false: var value = "false"; var flag = value = = = "False"? False:true;

Conversion of JS type to string and Boolean type