How to call a Stored Procedure?

Ok I will tell you how to call a stord procedure
Imagine that we Create a stored procedure as follow:

CREATE PROCEDURE GetUser
@UserId int      --Input paramerter
AS
SELECT * FROM UserTable WHERE UserID = @UserId
RETURN
GO
It is a simple stored procedure to be invoked by C# or VB.Net code
This is the code:
first include
using System.Data.SqlClient;

then

SqlConnection oConnection;
           try
           {
               //Put the connection string instead of ...
               oConnection = new SqlConnection("...");
               SqlCommand oCommand = new SqlCommand("GetUser", oConnection);
               //Precise that the type is stored procedure
               oCommand.CommandType = System.Data.CommandType.StoredProcedure;
               //You have to define an sqlparameter
               SqlParameter myParam = new SqlParameter("@UserId", System.Data.SqlDbType.Int);
               oCommand.Parameters.Add(myParam.Value);
           }
           finally
           {
               oConnection.Close();
           }
The most imporant remark, It is very dangerous that the sored procedure recieve parameters directly from  a text, your application can be vicitim of sql injection so I advise you use the sqlparameter object to be more secure