Xbasic

STRUCT_SET Function

STRUCT_SET() is deprecated and slated for removal in a future release.

Syntax

Structure as P = STRUCT_SET(C stucture_name[,B blob])

Arguments

stucture_name: The name of a structure created with a DECLARESTRUCT definition. Character
blob: Optional. Default = Null. The data to put into the structure.

Description

STRUCT_SET() creates a packed structure based on a DECLARESTRUCT definition, and optionally reads blob data to initialize the packed structure. This is useful for interpreting binary data read in from files.

Example

This following snippet of code reads the bitmap header structure from a bitmap file declare into the bitmap file header structure.

declarestruct BITMAPFILEHEADER C2Type, L1Size, W2Reserved, L1OffBits
? name of bitmap file is stored in a character variable
dim shared bitmapfilename as C
? open the bitmap file
f = file.open(bitmapfilename, FILE_RO_SHARED)
? use STRUCTURE_SET with no blob to create a structure
bitmapfile = struct_set("BITMAPFILEHEADER")
? which we then use to create a blob
bitmapfiledata = struct_get(bitmapfile)
?which we use to determine the size we need to read
bitmapfiledata = f.readb(bitmapfiledata.size() )
? convert the blob to the structure
bitmapfile = struct_set("BITMAPFILEHEADER", bitmapfiledata)
? close the file
f.close()