How to get the EF Core Connection String?

Time needed: 10 minutes.

How to extract the connectionstring from your Database Context in C#?

1. Include the following using statements

   
   using Microsoft.Data.SqlClient;
using Microsoft.EntityFrameworkCore;

2. Instantiate your DbContext (or inject it)

   Whatever you do, just have it set – this is the variable we’ll be using later on as well:
   
   // Injected in the constructor of the controller
// or instantiated in the code
ApplicationDbContext db;

3. Get the connection and access ConnectionString property

   Like shown below:
   
   // Fetch the DbConnection object and grab its Connection String
db.Database.GetDbConnection().ConnectionString
   
   Oh – a quick word of advice: The connection string will contain your password. Don’t log it anywhere as is. If you plan to push it to Application Insights or something, remove the password from the string before doing that.

4. (Optional) Sanitize your connection string to remove the password 😅

   In case you’re displaying or logging this information somewhere, you need to (at the very least) remove the password. Below, I’m displaying one possible way to do that:
   
   Regex r = new Regex("Password='.+'");
string dummyPassword = "Password='Password123'";
string cs = db.Database.GetDbConnection().ConnectionString;
string csSanitized= r.Replace(cs, dummyPassword);
_monitor.TrackEventDebug("ReadOnlyDbContext", "ConnectionString", csSanitized);