To print Barcode in C#, you need both barcode true type font and cruflbcsn.dll.
To get cruflbcsn.dll, you can either download it from Barcode C#.,
or you can generate cruflbcsn.dll if you already have cruflbcs.dll.
tlbimp is a utility of Windows SDK. It converts type definitions of a COM object to equivalent definitions in a common language runtime assembly that you can use in C#.
tlbimp cruflbcs.dll /out:cruflbcsn.dll
Add reference to cruflbcsn.dll from your C# project first.
Then use code snippet below to get Code 39 Barcode in C#
using cruflbcsn;
cruflbcsn.ILinear pLinear= new CLinear();
textBox2.Text = pLinear.Code39(textBox1.Text);