Yes you can is the simple answer.
With your CrystalReport you pass the dataset into it:
MyReport.SetDataSource(myDataSetObject)
Then pass your report into the appropriate viewer control web or Windows UI.
Be careful with large amounts of data as this makes a copy of the entire dataset, but of course has the advantage of no DB round trip.
You will have to create a dataset .xsd file within the .NET project for the crystal designer to work from as it will never be directly connected to any real database.
Each DataTable in the DataSet will need a sub-report to process the data, if you have any.
If you get issues with no data in the sub-reports then set the datasource for each.