Public Member Functions | Public Attributes

nsIArray Interface Reference

nsIArray More...

import "nsIArray.idl";

Inheritance diagram for nsIArray:

List of all members.

Public Member Functions

void queryElementAt (in unsigned long index, in nsIIDRef uuid,[iid_is(uuid), retval] out nsQIResult result)
unsigned long indexOf (in unsigned long startIndex, in nsISupports element)
nsISimpleEnumerator enumerate ()
 enumerate the array

Public Attributes

readonly attribute unsigned long length

Detailed Description


An indexed collection of elements. Provides basic functionality for retrieving elements at a specific position, searching for elements. Indexes are zero-based, such that the last element in the array is stored at the index length-1.

For an array which can be modified, see nsIMutableArray below.

Neither interface makes any attempt to protect the individual elements from modification. The convention is that the elements of the array should not be modified. Documentation within a specific interface should describe variations from this convention.

It is also convention that if an interface provides access to an nsIArray, that the array should not be QueryInterfaced to an nsIMutableArray for modification. If the interface in question had intended the array to be modified, it would have returned an nsIMutableArray!

null is a valid entry in the array, and as such any nsISupports parameters may be null, except where noted.


Member Function Documentation

nsISimpleEnumerator nsIArray::enumerate (  ) 

enumerate the array

a new enumerator positioned at the start of the array
NS_ERROR_FAILURE if the array is empty (to make it easy to detect errors)
unsigned long nsIArray::indexOf ( in unsigned long  startIndex,
in nsISupports  element 


Get the position of a specific element. Note that since null is a valid input, exceptions are used to indicate that an element is not found.

startIndex The initial element to search in the array To start at the beginning, use 0 as the startIndex
element The element you are looking for
a number >= startIndex which is the position of the element in the array.
NS_ERROR_NOT_FOUND if the element was not in the array.
void nsIArray::queryElementAt ( in unsigned long  index,
in nsIIDRef  uuid,
[iid_is(uuid), retval] out nsQIResult  result 


Retrieve a specific element of the array, and QueryInterface it to the specified interface. null is a valid result for this method, but exceptions are thrown in other circumstances

index position of element
uuid the IID of the requested interface
result the object, QI'd to the requested interface
NS_ERROR_NO_INTERFACE when an entry exists at the specified index, but the requested interface is not available.
NS_ERROR_ILLEGAL_VALUE when index > length-1

Member Data Documentation

readonly attribute unsigned long nsIArray::length


number of elements in the array.

The documentation for this interface was generated from the following file: