you didnt read documentation: section "Passing own connection string"
  public class ReportScript
  {
    private void _StartReport(object sender, EventArgs e)
    {
      String connection = Report.GetParameterValue("Connection").ToString();
      Report.Dictionary.Connections[0].ConnectionString = connection;
    }
  }
the designer is called via my application therefore the parameters are sended, it could be fine that the designer takes care of the parameters in the preview mode when it's called from the appli.
i think the documentation quite clear, do not change the connection string via parameter.
// in my application
FastReport.Report report = new FastReport.Report();
report.Preview = previewControl1;Â Â Â Â Â Â Â Â Â Â Â Â
report.Load(@"d:\untitled.frx");
report.Dictionary.Connections[0].ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=d:\data.mdb";
// run designer
report.Design();
// show in previewcontrol
report.Show();
Comments
thanks for your fast reply, very appreciated.
but this doesn't solve the problem (in designer/preview, works fine directly from the app) :