Exception While creating Crystal Reports

Question

Hi all
           I have a Problem While Creating Crystal Reports
                               The Exception was 
The Exception is:-Exception :: System.InvalidCastException: Unable to cast object of type 'System.Data.DataTable' to type 'System.Data.DataView'.


The crystal Reports Producing code When i click the button was

 try

            {

                System.Data.DataTable table = ((DataView)dataGridViewPOR.DataSource).Table;

                POCrystalReport crystal = new POCrystalReport();

                crystal.SetDataSource(table);

                this.POCrystalReportViewer.ReportSource = crystal;

            }
The Exception Raised in the highlighted line .I used this code many times.but exception raisweed this time
please solve my issue.

NagaRaju T