using DevExpress.XtraReports.UI;
using DevExpress.XtraPrinting.BarCode;
// ...

private void button1_Click(object sender, System.EventArgs e) {
    XtraReport1 report = new XtraReport1();

    // Create a barcode control.
    XRBarCode barcode = new XRBarCode();

    // Set the barcode's type to Codabar.
    barcode.Symbology = new CodabarGenerator();

    // Adjust the Codabar barcode's main properties.
    barcode.Text = "0123456789";
    barcode.Width = 300;
    barcode.Height = 100;

    // Adjust the Codabar barcode's specific properties.
    ((CodabarGenerator)barcode.Symbology).StartStopPair = CodabarStartStopPair.BN;
    ((CodabarGenerator)barcode.Symbology).WideNarrowRatio = 2.5F;

    report.Detail.Controls.Add(barcode);
    report.ShowPreview();
}

Imports DevExpress.XtraReports.UI
Imports DevExpress.XtraPrinting.BarCode
' ...

Private Sub Button1_Click(sender As Object, e As System.EventArgs) _
Handles Button1.Click
    Dim report As New XtraReport1()

    ' Create a barcode control.
    Dim barcode As New XRBarCode()

    ' Set the barcode's type to Codabar.
    barcode.Symbology = New CodabarGenerator()

    ' Adjust the Codabar barcode's main properties.
    barcode.Text = "0123456789"
    barcode.Width = 300
    barcode.Height = 100

    ' Adjust the Codabar barcode's specific properties.
    CType(barcode.Symbology, CodabarGenerator).StartStopPair = CodabarStartStopPair.BN
    CType(barcode.Symbology, CodabarGenerator).WideNarrowRatio = 2.5

    report.Detail.Controls.Add(barcode)
    report.ShowPreview()
End Sub