nunit assert.throws code example
Example: nunit expect exception
[Test]
public void TransferWithInsufficientFunds()
{
Account source = new Account();
source.Deposit(200m);
Account destination = new Account();
destination.Deposit(150m);
Assert.That(() => source.TransferFunds(destination, 300m),
Throws.TypeOf<InsufficientFundsException>());
}