JScript  

in Operator

Tests for the existence of a property in an object.

result = property in object

Arguments

result
Required. Any variable.
property
Required. An expression that evaluates to a string expression.
object
Required. Any object.

Remarks

The in operator checks if an object has a property named property. It also checks the object's prototype to see if the property is part of the prototype chain.

Requirements

Version 1

See Also

Operator Precedence | Operator Summary