L_INT pEXT_CALLBACK YourFunction(pVector, pLayer, pUserData)
Processes each vector layer enumerated by the L_VecEnumLayers function.
Pointer to the vector handle that contains the layers to enumerate.
Pointer to the vector layer being processed.
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 the calling function.)
Keep in mind that this is a void pointer, which must be cast to the appropriate data type within your callback function.
Value | Meaning |
---|---|
SUCCESS | The function was successful. |
< 1 | An error occurred. Refer to Return Codes. |
The L_VecEnumLayers function calls the callback function as it gets the handle of each vector layer.
Required DLLs and Libraries