刷卡问题

Question

刷卡后 combobox中有了卡号 焦点就到了textbox上面 
那这个要写在什么事件里呢还有呀 谁有那个打印超市那种小票的代码
要打印的东西是写在一个tabcontrol里面的
网上好多代码。。看不懂 汗
谁有谁有 帮帮我吧 无限感激

Answer 1

用一个DataGridview显示商品信息,然后据此打印,
我试过了,你选择好小票打印机为默认打印机,打出来的效果还可以,不过你要把代码写得好看点
private void print(PrintPageEventArgs e)
        {
            float x = 0f;
            float y = 0f;
            Graphics g = e.Graphics;
            Font TitleFont = new Font("宋体", 9, FontStyle.Bold);
            string TitleText = "某某超市(某某店)";
            SizeF TitleSize = g.MeasureString(TitleText, TitleFont);
            float TitleX = (e.PageBounds.Width - TitleSize.Width) / 2;
            g.DrawString(TitleText, TitleFont, Brushes.Black, TitleX, y);
            y += TitleFont.Height + 2f;
            g.DrawString("单据号" + Job.DanJuHao, TitleFont, Brushes.Black, x, y);
            g.DrawString("时间" + DateTime.Now.ToShortTimeString(), TitleFont, Brushes.Black, x + 121f, y);
            y += TitleSize.Height + 1f;
            g.DrawString("商品名称", TitleFont, Brushes.Black, x, y);
            g.DrawString("售价", TitleFont, Brushes.Black, x + 70f, y);
            g.DrawString("数量", TitleFont, Brushes.Black, x + 111f, y);
            g.DrawString("金额", TitleFont, Brushes.Black, x + 144f, y);
            for (int i = 0; i < dataGridView1.Rows.Count; i++)
            {
                y += TitleSize.Height;
                g.DrawString(dataGridView1[1, i].Value.ToString(), TitleFont, Brushes.Black, x, y);
                g.DrawString(dataGridView1[5, i].Value.ToString(), TitleFont, Brushes.Black, x + 70f, y);
                g.DrawString(dataGridView1[4, i].Value.ToString(), TitleFont, Brushes.Black, x + 118f, y);
                g.DrawString(dataGridView1[7, i].Value.ToString(), TitleFont, Brushes.Black, x + 144f, y);
            }
            y = y + TitleSize.Height;
            g.DrawString("合计：", TitleFont, Brushes.Black, x, y);
            g.DrawString(textBox数量.Text, TitleFont, Brushes.Black, x + 118f, y);
            g.DrawString(textBox应收.Text, TitleFont, Brushes.Black, x + 144f, y);
            y = y + TitleSize.Height;
            float YS = float.Parse(textBox实收.Text.Trim());
            string TempText = "应收：" + textBox应收.Text;
            g.DrawString(TempText, TitleFont, Brushes.Black, x, y);
            y += TitleSize.Height;
            TempText = "实收：" + YS.ToString("f2");
            g.DrawString(TempText, TitleFont, Brushes.Black, x, y);
            y += TitleSize.Height;
            TempText = "找零：" + textBox找零.Text;
            g.DrawString(TempText, TitleFont, Brushes.Black, x, y);
            //y = y + TitleSize.Height;
            //g.DrawString("三天内可凭此电脑小票退换货", TitleFont, Brushes.Black, x, y);
            string End = "——谢谢惠顾——";
            TitleSize = g.MeasureString(End, TitleFont);
            x = (e.PageBounds.Width - TitleSize.Width) / 2;
            g.DrawString(End, TitleFont, Brushes.Black, x, y + TitleSize.Height );
        }

Answer 2

写在TextChanged事件里:private void comboBox1_TextChanged(object sender, EventArgs e)
        {
            if (comboBox1.Text == "条件")
                textBox1.Select();//获取焦点(激活)
        }

Answer 3

C# 
private void comboBox1_TextChanged(object sender, EventArgs e) 
        {if (comboBox1.Text ！=" ") 
                textBox1.Focus();
        } 

Answer 4

应该是KEYDOWN
卡号后会自动加个回车

Answer 5

 private void comboBox2_TextChanged(object sender, EventArgs e)
        {
       /*    if (comboBox2.Text == "2009577813270007")
           {
              
                textBox1.Select();//获取焦点(激活)
            }*/
            
        string sql = "select * from ConsumptionCardInfor where 顾客编号='" +memberid  + "'";
            mycon.Open();
            SqlCommand cmd = new SqlCommand(sql, mycon);
            SqlDataReader sdr = cmd.ExecuteReader();
         
            if  (sdr.Read())
            {                if (comboBox2.Text == sdr["卡号"].ToString())
                {                    textBox1.Select();//获取焦点(激活)
                }
                else
                {
                    MessageBox.Show("异常卡！");
                    comboBox2.Text = "";
                    comboBox2.Select();
                }
                
              
            }
            sdr.Close();
          mycon.Close();
        }
为什么老是说连接未关闭 ？

Answer 6

sqldataReader是不能关连接的

Answer 7

为什么老是说mycon的连接未关闭
本来好好的 改点别的代码 前面就出现这个错误了 而且是反复在不同的地方出现
谁能教教我 怎么写才能不出这个错