How do I connect C# to SAP GUI?

For those who want to Automate the SAP GUI and are only able to do so through VBA and VB.Net. Here is a simple solution to automate SAP using C#:

First add two references:
SAPFEWSELib
SapROTWr <---- This one is located in the folder where SAP was installed.

Then add the using statements:

using SAPFEWSELib;
using SapROTWr;

Once those are added, add the following to a button:

//Get the Windows Running Object Table
SapROTWr.CSapROTWrapper sapROTWrapper = new SapROTWr.CSapROTWrapper();
//Get the ROT Entry for the SAP Gui to connect to the COM
object SapGuilRot = sapROTWrapper.GetROTEntry("SAPGUI");
//Get the reference to the Scripting Engine
object engine = SapGuilRot.GetType().InvokeMember("GetScriptingEngine", System.Reflection.BindingFlags.InvokeMethod, null, SapGuilRot, null);
//Get the reference to the running SAP Application Window
GuiApplication GuiApp = (GuiApplication)engine;
//Get the reference to the first open connection
GuiConnection connection = (GuiConnection)GuiApp.Connections.ElementAt(0);
//get the first available session
GuiSession session = (GuiSession)connection.Children.ElementAt(0);
//Get the reference to the main "Frame" in which to send virtual key commands
GuiFrameWindow frame = (GuiFrameWindow)session.FindById("wnd[0]");

This example works exactly like the Visual Basic Version does.


If you want to enter text into a text field within SAP, you must explicitly cast the object into the correct variable type

an example of entering an order number into CO02 Transaction, would be:

GuiTextField ordNum = (GuiTextField)session.FindById("wnd[0]/usr/ctxtCAUFVD-AUFNR");
ordNum.Text = textBox1.Text;
frame.SendVKey(0);