JavaScript simple and efficient notation (irrelevant version)

When a person works, the code wants to write how to write (laughter), with the same position partners, will find that the two people "write" difference.

One, string to integer such as "1"----1

Writing One: string-0

Notation Two: ~~string (√)

Second, rounding

Notation One: (number). ToFixed (2) (four homes six into five considerations)

Notation Two: Math.Round (number) (√)

Third, the binary

Notation One: 10000


Notation Two: 1e7 (√)

Four, default value

Notation One: if () else{}

Two: var var = var1 | | ""; or three-dimensional expression (√)

V: Determine if the variable is Boolean (True or false) in the If Judgment

One: var = = False

Notation Two:!var (√)

JavaScript simple and efficient notation (irrelevant version)