[size=medium]Since constructor functions define new categories or classes of objects, the constructor property can help
determine the type of an object. For example, you might use code like the following to determine the type
of an unknown value:
The instanceof operator checks the value of the constructor property, so the code above could also be
written:
[/size]
determine the type of an object. For example, you might use code like the following to determine the type
of an unknown value:
if ((typeof o == "object") && (o.constructor == Date))
// Then do something with the Date object...
The instanceof operator checks the value of the constructor property, so the code above could also be
written:
if ((typeof o == "object") && (o instanceof Date))
// Then do something with the Date object...
[/size]
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Extending Built-in Types
2009-01-08 13:55 725The Function.apply( ) method is ... -
Breakpoints using closures
2009-01-07 13:43 869// // This function implements ... -
Private properties with closures
2009-01-07 13:13 760// // This function adds proper ... -
Constructor Functions
2009-01-07 00:42 758the new operator creates a new ... -
Functions as Methods
2009-01-07 00:39 804When a function is invoked as a ... -
The callee Property
2009-01-07 00:02 664In addition to its array elemen ... -
Variable-Length Argument Lists: The Arguments Obje
2009-01-06 23:06 787The Arguments object has one ve ... -
Function Literals
2009-01-06 21:50 702Although function literals crea ... -
Nested Functions
2009-01-06 21:09 767Nested functions may be defined ... -
Deleting Array Elements
2009-01-05 22:11 566The delete operator sets an arr ... -
Reading and Writing Array Elements
2009-01-05 22:00 763Note that array indexes must be ... -
The valueOf() Method
2009-01-05 18:05 741... -
The toLocaleString() Method
2009-01-05 18:02 851In ECMAScript v3 and JavaScript ... -
the empty statement
2009-01-05 00:29 786[size=medium]When you intention ... -
with
2009-01-05 00:27 683[size=medium]The with statement ... -
try/catch/finnaly
2009-01-05 00:17 890If control leaves the try bloc ... -
throw
2009-01-04 23:56 691The tHRow statement has the fol ... -
return
2009-01-04 23:52 815If a function executes a return ... -
functions
2009-01-04 23:48 789[size=medium]Technically speaki ... -
Labels
2009-01-04 23:01 706Label names are distinct from v ...
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