New shared collection

Home

4D v20 R7


New shared collection {( value {; value2 ; ... ; valueN} )} -> Function result

Parameter	Type	Description
value		Shared collection's value(s)
Function result	Collection	New shared collection

Description

The New shared collection command creates a new empty or prefilled shared collection and returns its reference. Adding an element to this collection must be surrounded by the Use...End use structure, otherwise an error is generated. Reading an element without a structure is, however, possible.

Note: For more information on shared collections, please refer to the Shared objects and shared collections page.

If you do not pass any parameters, New shared collection creates an empty shared collection and returns its reference.

You must assign the returned reference to a 4D variable declared with the _O_C_COLLECTION command.

Note: Keep in mind that _O_C_COLLECTION declares a variable of the Collection type, but does not create a collection.

Optionally, you can prefill the new shared collection by passing one or several value(s) as parameter(s). Otherwise, you can add or modify elements subsequently through object notation assignment (see example).

If the new element index is beyond the last existing element of the shared collection, the collection is automatically resized and all new intermediary elements are assigned a null value.

You can pass any number of values of the following supported types:

number (real, longint...). Number values are always stored as reals.
text
booelan
date
time (stored as number of milliseconds - real)
null
shared object(*)
shared collection(*)

Note: Unlike standard (not shared) collections, shared collections do not support pictures, pointers, and objects or collections that are not shared.

(*)When a shared object or collection is added to a shared collection, they share the same locking identifier. For more information on this point, refer to the About the locking identifier (how shared groups work) section.

Example

 $mySharedCol:=New shared collection("alpha";"omega")

 Use($mySharedCol)

    $mySharedCol[1]:="beta"

 End use