How can i add a hook for the before when step in specflow ?

Question

HI,

 

ive got the following specflow test:

 

 Scenario Outline: Admin adds an alternate numbers entry with a phonenumber successfully
Given the BW User is logged in with a <userlevel> Level Account
And the AddAlternateNumbersEntry query parameter contains an existing userid within the scope of the BW User
And the AddAlternateNumbersEntry post body contains an available phonenumber
When the BW User submits the AddAlternateNumbersEntry request
Then HTTP 201 should be returned
And a new alternate numbers entry should be added

Examples: User Levels
| userlevel |
| System |
| Service Provider |
| Group |

 

Now i want to add a hook that only runs BEFORE the WHEN ste not the given and the then steps.

 How can i do this ???