Throw Argument Null Exception

ArgumentNullException.cs

// before C#10 and .NET6
//
public void GetSomething(string id)
{
  if (id is null)
  {
    throw new ArgumentNullException(nameof(id));
  }
  
  // ... and here your code to get some data
}

// how it looks like now
//
public void GetSomething(string id)
{
  ArgumentNullException.ThrowIfNull(id);
  
  // ... and here your code to get some data
}

// or using third-party package [ https://github.com/mantinband/throw ]
//
public void GetSomething(string id)
{
  id.ThrowIfNull();
  
  // ... and here your code to get some data
}