INOTE

How Javascript convert an object to a primitive using OPCA

Using valueOf

  • Used if method valueOf() exists.
  • If valueOf() returns a primitive, the object is converted to this value
  • But most of the native objects when calling the valueOf() method returns the object itself. So the toString() method is used more often

Using toString()

  • Used if method toString() exists.
  • If toString() returns a primitive, the object is converted to this value
  • Date object use toString() instantly instead of valueOf
  • The plain JavaScript object, {} or new Object(), usually is converted to "[object Object]".
  • An array is converted to by joining it’s elements with "," separator.
    • For example [1, 3, "four"] is converted to "1,3,four"