Xbasic

BLOB Functions

Description

Blob Functions query and manipulate binary data.

Name
Description
*gunzip_blob Function

Decompress blob using gzip.

*gzip_blob Function

Compress blob using gzip.

a5storage_getitem_as_blob Function

Retrieves data from an item in storage and puts the data in a blob variable.

BlobCompare Function

Performs a byte by byte comparison of the two blobs. Returns 0 if equal, 1 if the left is greater, -1 if the right is greater.

BlobEqual Function

Returns .t. if the binary objects are the same length and values.

CHAR_TO_BLOB Function

CHAR_TO_BLOB() returns the blob equivalent of the original character string.

PROPERTY_FROM_BLOB Function

Property read from blob data that was orginally created with PROPERTY_TO_BLOB()

property_from_blob_const Function

Creates a readonly property from blob - used to store read-only definitions.

PROPERTY_FROM_BLOB_EXTRACT Function

Allows a single property in a binary object created with property_to_blob().

PROPERTY_TO_BLOB Function

Dump pointer contents (can be variable frame) to a blob - optional limit to 'fields'.

STRUCT_GET Function

Converts a packed structure to a blob.

STRUCT_SET Function

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.

Manipulating Blob Data 

Additional functions that are useful for manipulatng blob data.

  • FILE.FROM_BLOB() - Creates a Windows Bitmap (.BMP) or JPEG (.JPG) file from binary data.

  • FILE.TO_BLOB() - Reads a binary file from disk into a blob variable. The data can be in either Windows Bitmap (.BMP) or JPEG (.JPG) formats.

  • INCREMENT_VALUE() - Increments the value of a variable by 1.

  • table.RECORD_DATA_GET() - Copies all the field values from Record_Number (or the current record if Record_Number is not specified) to a blob variable.

  • table.RECORD_DATA_SET() - Copies all the field values from the blob variable, Record_Data, into the current record.

See Also