DevExpress XRPdfContent.Source

using System.IO;
using DevExpress.XtraReports.UI;
using DevExpress.XtraReports.Expressions;
// ...
// Create a report that has a Detail band and uses Landscape page orientation.
XtraReport report = new XtraReport(){
    Landscape = true,
    Bands = {
        new DetailBand() {
            Name = "DetailBand",
            HeightF = 25,
        }
    }
};
// Create an XRPdfContent class instance.
XRPdfContent pdfContent = new XRPdfContent();
// Assign binary PDF content to the XRPdfContent's Source property.
pdfContent.Source = System.IO.File.ReadAllBytes("MasterDetailReport.pdf");
// Add the XRPdfContent control to the Detail band.
report.Bands[BandKind.Detail].Controls.Add(pdfContent);