How can I stub IDBconnection

Question

I am writting Unit Test for my database connection.

I have following class

Public class A
{
    public IDbConnection _dbConnection;

    public A()
    {         


        

Answer 1

You can easely use the constructor to of class A to insert your dependencies, add the following constructor to class A:

public A(IDBConnection connection)
{
   _dbConnection = connection;
}

Then you test will look like:

[TestMethod]
public void TestMethod1()
{
    StubIDbConnection stubIDbConnection = new StubIDbConnection();
    stubIDbConnection.Execute =(null) => -1;
    var a = new classA(stubIDbConnection);
    int answer = a.ExecuteNoneQuery(null);
    Assert.AreEqual(-1,answer);
}