The service was attended by his friends and family and several hundred members of Thames Valley Police, with more lining the streets of Oxford as his coffin was given a 15 minute procession.
PC Harper was killed on 15th August while attending a burglary on the outskirts of a Berkshire village.
He died from multiple injuries after being dragged under a van.
The 28 year old lost his life four weeks after he got married to his partner Lissie, who read 1 Corinthians 13 at the service.
The Very Revd Prof. Martyn Percy, Dean of Christ Church, gave the address, saying: "Andrew's completely unexpected, sudden and tragic death reminds us of the routine risks that police officers take each day.
"No-one ever anticipates an ordinary call-out ending in such tragedy. To all of you here, gathered from Thames Valley Police, we extend not only our sympathy to you in the loss of such a valued colleague, but also our deepest thanks for your sacrificial service to our communities. Such a terrible loss brings us face to face with the risks you take on our behalf."
Speaking about the famous chapter about love in the Bible, he said: "Down the ages we have come to see this love as the highest Christian virtue. As God stooped down in Christ to love humanity, so God's call to his people was to exercise a love for others that was not about self-gain, but rather about self-giving.
"Charity is Christian love in action; a way of being for others that treats them with respect and dignity, and has concern for their needs and well-being. This is something that Andrew practiced. And it is not just personal, for it goes to the heart of policing too."
Henry Long, 18, from Mortimer in Reading, and two 17-year-old boys, who cannot be named because of their age, have been charged with murder and conspiracy to steal a quad bike.
Thomas King, 21, from Basingstoke, is also accused of conspiracy to steal a quad bike.
Lissie Harper said in her eulogy: "We managed to pack so many amazing memories into the last 13 years, travelling the world, buying a house and getting married. You had a contagious love for life, filling each day with laughter and appreciating all the little things.
"You have always been a protector. Whether in your role of big brother, fierce friend, loving husband or keeper of peace among the public, keeping everyone safe was your priority, not only in your job but your family too. Everything was always okay when you were around."
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