The Buddhist teachings are three-fold, namely:
Concentration; unified non-judgmental awareness; unconditional love; unworldly 'heavenly' states of mind called 'jhana'.
Wisdom of four noble truths; three characteristics; not-self; emptiness of self; natural elements.
Christianity & Buddhism are essentially the same in respect to 1. morality & 2. unified non-judgmental love however different in relation to 3. wisdom.
In fact, it is highly probable the Christian teachings that set Christianity apart from Judaism come from Buddhism & post-Buddhist-Brahmanism (Hinduism). 'Brahma' is the 'Father of All' and the Buddha (in the Tevijja Sutta) taught to non-Buddhist Brahmans that the way or path to Brahma was to radiate limitless unconditional love in all directions, which is essentially the same as what Jesus taught, namely: "My love is the Way to the Father" (John 14.6) & "God is love" (1 John 4:8).
Buddhism differs from Christianity in that is does not believe in a creator God and believes everything in life, whether physical, mental or Nirvana, is merely natural elements ('dhatu'). Buddhism is strictly impersonal ('anatta') where as Christianity believes in personality, including the personality of God.
The following book makes a comparison however I doubt it is completely objective since it seeks to make mutual understanding between religions: Christianity & Buddhism - Buddhadasa Indapanno