Sunan Ibn Majah Book 33, Hadith 147
"When the Messenger of Allah (ﷺ) saw something he liked, he would say: 'Al-hamdu lillahil-ladhi bi ni'matihi tatimmus-salihat (Praise is to Allah by Whose grace good deeds are completed).' And if he saw something that he disliked, he would say: 'Al-hamdu lillahi 'ala kulli hal (Praise is to Allah in all circumstances).'"
his father said: "I prayed with the Prophet (ﷺ) and a man said: 'Alhamdu lillahi hamdan kathiran tayyiban mubarakan fihi (Praise is to Allah, much, good and blessed praise).' When the Prophet (ﷺ) finished praying, he said: 'Who said that?' The man said: 'It was me, but I did not mean anything but good.' He said: 'The gates of heaven were opened because of it and nothing prevented it from reaching the Throne.'"
the Prophet (ﷺ) used to say: "Al-hamdu lillahi 'ala kulli hal. Rabbi a'udhu bika min hali ahlin-nar (Praise is to Allah in all circumstances, O Allah, I seek refuge with You from the situation of the people of Hell)."