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4D v14.3

ARRAY BLOB


ARRAY BLOB ( arrayName ; size {; size2} )

Parameter	Type	Description
arrayName	Array	Name of array
size	Longint	Number of array elements or Number of arrays if size2 is specified
size2	Longint	Number of 2D array elements

Description

The ARRAY BLOB command creates and/or resizes an array of Blob type elements in memory.

The arrayName parameter is the name of the array.

The size parameter is the number of array elements.

The size2 parameter is optional. If you pass it, this command creates a two-dimensional array. In this case, size specifies the number of rows and size2 the number of columns in each array. Each row in a two-dimensional array can be processed both as an element and an array. This means that when you work with the first dimension of a two-dimensional array, you can insert and remove entire arrays using other commands in this theme.

When you apply the ARRAY BLOB command to an existing array:

If you enlarge its size, existing elements are not changed and new elements are initialized to an empty BLOB (BLOB size= 0).
If you reduce its size, elements at the "bottom" of the array are deleted and lost.

Example 1

This example creates a process array containing 100 BLOB-type elements:

ARRAY BLOB(arrBlob;100)

Example 2

This example creates a local array of 100 rows each containing 50 BLOB-type elements:

ARRAY BLOB($arrBlob;100;50)

Example 3

This example creates a local array of 100 rows each containing 50 BLOB-type elements. The $vByteValue variable receives the 10th byte of the BLOB placed in the 7th column and the 5th row of the BLOB array:

 C_INTEGER($vByteValue)

 ARRAY BLOB($arrValues;100;50)

 ...

 $vByteValue:=$arrValues{5}{7}{9}