asp.net core 2.0 - Value cannot be null. Parameter name: connectionString

Question

I had the following error in package manager console when Add-Migration

Value cannot be null. Parameter name: connectionString

Answer 1

I'm stupid and I had typo

{
  "Conn*ce*tionStrings": {
    "DefaultConnection": "Data source=***.db"
  },

changed it to

{
  "ConnectionStrings": {
    "DefaultConnection": "Data source=datingapp.db"
  },