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Called to let the user know that an error occurred during the properties set operation and lets the user aborts or retry. The address of this callback is passed as an argument in L_WiaSetProperties function.
#include "ltwia.h"
L_INT pEXT_CALLBACK YourFunction(hSession, PropertyID, nError, uValueType, pValue, pUserData)
Handle to an existing WIA session. This handle is obtained by calling the L_WiaInitSession function.
The ID of the property that was set using the value specified in the pValue parameter.
The returned error code for certain property set.
The value type of the property. For a list of valid value types see Microsoft's documentation of the VARENUM enumeration.
Void pointer to the value used to set this property.
You need to cast this void pointer back to (L_INT) for all the properties in LWIAPROPERTIES structure except for the pguidFormat property, which should be cast to (GUID).
A void pointer that you can use to access a variable or structure containing data that your callback function needs. This gives you a way to receive data indirectly from the function that uses this callback function. (This is the same pointer that you pass in the pUserData parameter of L_WiaSetProperties.)
Keep in mind that this is a void pointer, which must be cast to the appropriate data type within your callback function.
| Value | Meaning |
|---|---|
| WIA_SUCCESS | The function was successful. |
| WIA_ABORT | The callback wants to abort the properties set process. |
| WIA_RETRY | The callback wants to retry the properties set process again. |
| < 1 | An error occurred. Refer to Return Codes. |
This feature is available in version 16 or higher.
Called to let the user know that an error occurred during the properties set operation and lets the user aborts or retry.
For an example, refer to L_WiaGetRootItem.