SqlConnection conn = new SqlConnection("Data Source=(local);Initial Catalog=MyDatabase;User ID=sa;Password=sa");
                     conn.Open();
                     SqlCommand comm = new SqlCommand();
          
                     comm.Connection =conn ; 
            
                     string sql = "";
                     sql = "CREATE   TABLE   tablename";
                     sql += "(   ";
                     sql += "date_in   datetime,";
                     sql += "user_id   int,";
                     sql += "myuser_name   varchar(200)";

                     sql += ")";
            
                     comm.CommandText = sql;
                     SqlParameter parm1 = new SqlParameter("@tablename", SqlDbType.VarChar, 20);
                     parm1.Value = ("tablename");
                     comm.Parameters.Add(parm1);
                     try
                       {
                
                             comm.ExecuteNonQuery();//这是执行语句
                             MessageBox.Show("成功创建表", "信息提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        }
                      catch (Exception ex)
                        {
                             MessageBox.Show(ex.Message, "信息提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        }
                      finally
                        {
                            conn.Close();
                        }