Get stored procedure parameters with datatype in C#

Question

I have developed a method but it don't return that this parameter is allow null or not.

means is it allows either @Param varchar(50) = null or @Param varchar(50)

my method is

	SqlConnection connection = new SqlConnection("connectionString");
SqlCommand cmd = newSqlCommand("Procedure Name", connection);

        cmd.CommandType = CommandType.StoredProcedure;
 
        conn.Open();
        SqlCommandBuilder.DeriveParameters(cmd);
 
        foreach (SqlParameter p in cmd.Parameters)
        {
            if (!p.ParameterName.Contains("RETURN_VALUE"))
                Response.Write("Param Name : " + p.ParameterName + " & Param DbType : " + p.DbType + " & Param Sql DbType : " + p.SqlDbType + " & Is Null : " + p.IsNullable + ". <br />");
        }
Please reply if any body find any solution.