Question about Stored Procedure Parameters

[Tim]

Hi,
I am using OleDb in a managed C++ application to
interact with a MS SQL Server. I am having trouble
filling in the parameters for a stored procedure I am
trying to call. This is the code I have:

command->set_CommandType(CommandType::StoredProcedure);
command->set_CommandText(S"UserLoginConnect");
OleDbParameter* nameParam = command->Parameters->Add
(S"@Name", OleDbType::VarChar);
nameParam->set_Value(userID);

userID is a String. When I compile this I get:

error
C2664: 'System::Data::OleDb::OleDbParameter::set_Value' :
cannot convert parameter 1 from 'std::string *'
to 'System::Object __gc *'
Cannot convert an unmanaged type to a managed type

Is there a way to convert a string to a __gc*? Or should
I be using another type of variable to hold information
other than strings? (BTW, I have tried using userID.c_str
() in place of userID to no avail)

Thank you,

-Tim