如何找出GetObject失败的原因？

Question

According to MSDN, GetObject returns 0 on failure. It does not say how to get additional information about the failure.

I've tried GetLastError , but it looks like it does not reflect the previous failure and returns 0 (ie ERROR_SUCCESS ) instead.

How do I get the failure reason when GetObject fails?

Answer 1

According to the documentation GetObject will not set the last error code. This is not necessary either, since you can easily deduce, which parameter is wrong:

If a call to GetObject fails passing NULL for lpvObject , you know the handle is wrong (either a handle to an object that no longer exists, or is of an unsupported type).

If the previous call succeeded, and a following call with the same GDI object handle fails, you know that you are passing an inappropriate buffer (either too small, or not properly aligned on a 4-byte boundary).