Item (UnicodeNamedArraylist property): Difference between revisions

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Regardless of the value of <var>UseDefault</var>, the presence of the item with the indicated name can be checked using the <var>[[Number (UnicodeNamedArraylist function)|Number]]</var> function, for example:
Regardless of the value of <var>UseDefault</var>, the presence of the item with the indicated name can be checked using the <var>[[Number (UnicodeNamedArraylist function)|Number]]</var> function, for example:
<p class="code">%num = %myLis:number(%key)
<p class="code">%num = %myLis:number(%key)
if %num then %name = %myLis:[[ItemByNumber (UnicodeNamedArraylist property)|itemByNumber]]
if %num then %name = %myLis:[[ItemByNumber (UnicodeNamedArraylist property)|itemByNumber]](%num)
...
...
</p>
</p>
</ul>
<li>As shown in the example in the [[UnicodeNamedArraylist class]] article, <var>UnicodeNamedArraylist</var> items are ordered alphabetically by their subscript names.  Accordingly, the <var>Item</var> method takes a Unicode string as it's argument.
<li>As shown in the example in the [[UnicodeNamedArraylist class]] article, <var>UnicodeNamedArraylist</var> items are ordered alphabetically by their subscript names.  Accordingly, the <var>Item</var> method takes a Unicode string as it's argument.
</ul>
</ul>

Revision as of 17:34, 21 July 2011

Value of named item (UnicodeNamedArraylist class)


Item is a ReadWrite property returns or sets the value of the item that has the specified subscript name in the UnicodeNamedArraylist.

For additional comments about the Item method in collections, see "Coding considerations for collections".

Syntax

%currentItem = uniNal:Item( unicode) uniNal:Item( unicode) = newItem Throws ItemNotPresent

Syntax terms

%currentItem A variable of the same type as specified on the uniNal declaration to contain the value of the specified uniNal item.
uniNal A UnicodeNamedArraylist object.
unicode A Unicode string that serves as a subscript to identify a uniNal item.
newItem A variable or value of the same type as specified on the uniNal declaration to be assigned to the specified uniNal item.

Usage notes

  • The Item keyword is not required. For example, in the request in the UnicodeNamedArraylist class example, %k('&sect;Apr':u) = 'Leo', for instance, is equivalent to:

    %k:Item('&sect;Apr':u) = 'Leo'

  • If the Item property is being set and there is already an item on the UnicodeNamedArraylist that has the specified name, that item is replaced. If the Item property is being set and there is no item on the UnicodeNamedArraylist that has the indicated name, the item is added.
  • If the Item property is being retrieved and there is no item on the UnicodeNamedArraylist that has the indicated name, the result is one of the following actions:
    • The request is cancelled if the UseDefault property value is False.
    • The Default value is returned if the UseDefault property is True.

    Regardless of the value of UseDefault, the presence of the item with the indicated name can be checked using the Number function, for example:

    %num = %myLis:number(%key) if %num then %name = %myLis:itemByNumber(%num) ...

  • As shown in the example in the UnicodeNamedArraylist class article, UnicodeNamedArraylist items are ordered alphabetically by their subscript names. Accordingly, the Item method takes a Unicode string as it's argument.

See also

  • The ItemByNumber method, described below, lets you retrieve or set an item using the item's ordinal number.
  • The NameByNumber function lets you retrieve or set an item using the item's subscript name.