4D v18
DOCUMENT TO BLOB
- 4D Language Reference
-
- BLOB
-
- BLOB Commands
- BLOB PROPERTIES
- BLOB size
- BLOB TO DOCUMENT
- BLOB to integer
- BLOB to list
- BLOB to longint
- BLOB to real
- BLOB to text
- BLOB TO VARIABLE
- COMPRESS BLOB
- COPY BLOB
- DECRYPT BLOB
- DELETE FROM BLOB
- DOCUMENT TO BLOB
- ENCRYPT BLOB
- EXPAND BLOB
- INSERT IN BLOB
- INTEGER TO BLOB
- LIST TO BLOB
- LONGINT TO BLOB
- REAL TO BLOB
- SET BLOB SIZE
- TEXT TO BLOB
- VARIABLE TO BLOB
DOCUMENT TO BLOB
| DOCUMENT TO BLOB ( document ; blob {; *} ) | ||||||||
| Parameter | Type | Description | ||||||
| document | String |
|
Name of the document | |||||
| blob | BLOB |
|
BLOB field or variable to receive the document | |||||
|
Document contents | |||||||
| * | Operator |
|
*** Obsolete, do not use *** | |||||
DOCUMENT TO BLOB loads the whole contents of document into blob. You must pass the name of an existing document that is not already open, otherwise an error will be generated. To let the user choose the document to be loaded into the BLOB, use the command Open document and the process variable document (see Example).
Compatibility Note: The optional * (resource fork management in older versions of Mac OS) is no longer supported in 4D as of 4D v16. For more information, see the Deprecated and Removed Features manual.
You write an Information System that enables you to quickly store and retrieve documents. In a data entry form, you create a button that allows you to load a document into a BLOB field. The method for this button could be:
$vhDocRef:=Open document("") ` Select the document of your choice
If(OK=1) ` If a document has been chosen
CLOSE DOCUMENT($vhDocRef) ` We don't need to keep it open
DOCUMENT TO BLOB(Document;[YourTable]YourBLOBField) ` Load the document
If(OK=0)
` Handle error
End if
End ifOK is set to 1 if the document is correctly loaded, otherwise OK is set to 0 and an error is generated.
- If you try to load (into a BLOB) a document that does not exist or that is already open by another process or application, the appropriate File Manager error is generated.
- An I/O error can occur if the document is locked, located on a locked volume, or if there is problem in reading the document.
- If there is not enough memory to load the document, an error -108 is generated.
In each case, you can trap the error using an ON ERR CALL interruption method.
Product: 4D
Theme: BLOB
Number:
525
Created: 4D v6
Storing documents, Resource fork, Data fork, Document
4D Language Reference ( 4D v18)
