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string

number

boolean

object

function

3?? ?? ??:

Object

Date

Array

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null

undefine

typeof ???

typeof ???? ???? JavaScript ??? ??? ??? ? ? ????.

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<html> <body> <script type="text/javascript"> var test=new Array(); if (test.constructor==Array) { document.write("This is an Array"); } if (test.constructor==Boolean) { document.write("This is a Boolean"); } if (test.constructor==Date) { document.write("This is a Date"); } if (test.constructor==String) { document.write("This is a String"); } </script> </body> </html>