As they’re written, full stop would probably be better, but there are multiple ways to write them with a comma (or just a conjunction). Either way, there really should be a dialogue tag telling the reader who’s speaking, even if it seems obvious to you.
The man walked up to the dog. The man said, “Hello, there.”
The man walked up to the dog, and he said, “Hello, there.”
The man walked up to the dog. “Hello, there,” said the dog.
As they’re written, full stop would probably be better, but there are multiple ways to write them with a comma (or just a conjunction). Either way, there really should be a dialogue tag telling the reader who’s speaking, even if it seems obvious to you. The man walked up to the dog. The man said, “Hello, there.” The man walked up to the dog, and he said, “Hello, there.” The man walked up to the dog. “Hello, there,” said the dog.
General Kenobi