When a non-null object is used in a Boolean context, it converts to true . When an object is used in a
string context, JavaScript calls the toString( ) method of the object and uses the string value returned
by that method. When an object is used in a numeric context, JavaScript first calls the valueOf( ) method
of the object. If this method returns a primitive value, that value is used. In most cases, however, the
valueOf( ) method returns the object itself. In this case, JavaScript first converts the object to a string
with the toString( ) method and then attempts to convert the string to a number.
string context, JavaScript calls the toString( ) method of the object and uses the string value returned
by that method. When an object is used in a numeric context, JavaScript first calls the valueOf( ) method
of the object. If this method returns a primitive value, that value is used. In most cases, however, the
valueOf( ) method returns the object itself. In this case, JavaScript first converts the object to a string
with the toString( ) method and then attempts to convert the string to a number.
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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 760the new operator creates a new ... -
Functions as Methods
2009-01-07 00:39 805When 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 567The 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 18:05 742... -
The toLocaleString() Method
2009-01-05 18:02 851In ECMAScript v3 and JavaScript ... -
The constructor Property
2009-01-05 17:51 789[size=medium]Since constructor ... -
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 ...
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