The ESignature object is a COM object that implements the IESignature interface. The ESignature object supports electronic signatures for FIX32 data sources, non-FIX32 data sources, and other actions, such as recipe download. You can create a script or another application that prompts the operator to enter an electronic signature using the ESignature object. This allows you to:
- Integrate with badge readers and other signing mechanisms.
- Sign for writes to OPC sources.
- Sign for other actions when writing to multiple data points, such as recipe download.
- The object can be instantiated by both VB/VBA and C/C++ code. You can call methods in the IESignature interface to:
- Determine if a tag requires a signature.
- Display the Electronic Signature dialog box.
- Validate a signature without displaying the Electronic Signature dialog box.
- Send a signed operator message to the audit trail.
NOTE: Do not use scripts that use signing from the Scheduler. Signing does not work well from the background task. This is also an important consideration when implementing scripts that call global subroutines.
ESignature methods support the following actions for all data sources:
- Initialize and display the Electronic Signature dialog box, validate signatures, and perform security checks based on information and settings passed in.
- Validate signatures and perform security checks for specific users based on user names, passwords, and settings passed in, without using the Electronic Signature dialog box.
- Send a signed operator message to the audit trail, logging the signature and action.
ESignature methods support the following actions for FIX32 data sources:
- Read electronic signature settings associated with the tag directly from the process database.
- Display the Electronic Signature dialog box based on those settings, validate the signature and perform security checks, write the value to the database or acknowledge an alarm or page of alarms, and send the signed operator message to the audit trail.
- Validate signatures and perform security checks for specific users based on user names, passwords, and settings passed in, without using the Electronic Signature dialog box, and then write the value to the database or acknowledge an alarm or page of alarms and send the signed operator message to the audit trail.
NOTE: In order to use the enumerations listed for the ESignature Object methods, you must reference the Electronic Signature type library in VBA.
