SqlConnection conn = new SqlConnection("Initial Catalog=student;Data Source=localhost;User ID=sa; Password=123456");
                conn.Open();
                SqlCommand cmd = new SqlCommand();
                = "insert into 基本信息表（studentno,studentname,xb,age,bj)values(@编号,@姓名,@性别,@年龄,@班级)";
                cmd.Connection = conn;
                cmd.Parameters.Add("@编号", SqlDbType.Int);//定义数据库数据类型
                cmd.Parameters.Add("@姓名", SqlDbType.NVarChar, 50);
                cmd.Parameters.Add("@性别", SqlDbType.NVarChar, 50);
                cmd.Parameters.Add("@年龄", SqlDbType.Int);
                cmd.Parameters.Add("@班级", SqlDbType.NVarChar, 50);
                cmd.Parameters["@编号"].Value = textBox1.Text.Trim();//赋值
                cmd.Parameters["@姓名"].Value = textBox2.Text.Trim();
                cmd.Parameters["@性别"].Value = comboBox1.Text.Trim();
                cmd.Parameters["@年龄"].Value = textBox3.Text.Trim();
                cmd.Parameters["@班级"].Value = comboBox2.Text.Trim();
                cmd.ExecuteNonQuery();//这里提示语法错误！System.Data.SqlClient.SqlException:“'（' 附近有语法错误。”
                conn.Close();//关闭数据库
                this.Close();//关闭form2窗口