The officer retreated and waited for backup to arrive at the scene.
When other officers arrived the alleged offender approached them while they were still in the vehicle and one officer was attacked through an open window, police said in a statement.
The officer raised his arm to protect himself but was stabbed through the window of the car.
He has cuts on his arm and is in a stable condition in hospital.
"The safety of staff is our priority, there is always a risk in policing but an assault on an officer protecting their community is an assault on the fabric of our community," Price said.
"Senior police and colleagues will be supporting the injured officer and his family."
One person has been arrested.