BLOB TO DOCUMENT
BLOB TO DOCUMENT ( document ; blob )
| Parameter | Type | Description | |
|---|---|---|---|
| document | Text | → | Name of the document |
| blob | Blob | → | New contents for the document |
Description
BLOB TO DOCUMENT rewrites the whole contents of document using the data stored in blob. You can pass the name of a document in document. If the document does not exist, the command creates it. If you pass the name of an existing document, make sure that it is not already open, otherwise an error is generated. If you want to let the user choose the document, use the commands Open document or Create document and use the process variable document (see example).
Example
You write an Information System that enables you to quickly store and retrieve documents. In a data entry form, you create a button which allows you to save a document that will contain the data previously loaded into a BLOB field. The method for this button could be:
$vhDocRef:=Create document("") // Save the document of your choice
If(OK=1) // If a document has been created
CLOSE DOCUMENT($vhDocRef) // We don't need to keep it open
BLOB TO DOCUMENT(Document;[YourTable]YourBLOBField) // Write the document contents
If(OK=0)
// Handle error
End if
End if
System variables and sets
OK is set to 1 if the document is correctly written, otherwise OK is set to 0 and an error is generated.
Error Handling
- If you try to rewrite a document that does not exist or that is already open by another process or application, the appropriate File Manager error is generated.
- The disk space may be insufficient for writing the new contents of the document.
- I/O errors can occur while writing the document.
In all cases, you can trap the error using an ON ERR CALL interruption method.
See also
Create document
DOCUMENT TO BLOB
Open document
Properties
| Command number | 526 |
| Thread safe | ✓ |
| Modifies variables | OK, error |