本文实例为大家分享了C#超市收银系统设计的具体代码，供大家参考，具体内容如下
1.登录界面
代码如下：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace 梦之翼小组项目
{
public partial class denglu : Form
{
public denglu()
{
InitializeComponent();
}
model db = new model(); //实例化数据库对象
private void button1_Click(object sender, EventArgs e)
{
string strConn = "Data Source=.;Initial Catalog=shopInfo;Integrated Security=True"; //连接数据库
SqlConnection Connection = new SqlConnection(strConn);
try
{
string sqlStr = "select userName,userPassword from register where userName=@userName"; //查询
DataSet ds = new DataSet();
Connection.ConnectionString = Connection.ConnectionString;
Connection.Open();
SqlCommand cmd = new SqlCommand(sqlStr, Connection);
cmd.Parameters.Add(new SqlParameter("@userName", SqlDbType.VarChar, 30)); //传参
cmd.Parameters["@userName"].Value = userName.Text; //给user文本框赋值
SqlDataReader dater = cmd.ExecuteReader();
if (userName.Text.Trim() == "") //如果user的值等于空
{
MessageBox.Show( "用户名不允许为空!");
}
else if (passWord.Text.Trim() == "") //同上
{
MessageBox.Show( "密码不能为空!");
}
else if (!dater.Read()) //如果输入的用户名没有被dater读到，则用户名不存在
{
MessageBox.Show( "用户名不存在！");
userName.Text = "";
passWord.Text = "";
}
else if (dater["userPassWord"].ToString().Trim() == passWord.Text.Trim()) //输入密码等于数据库密码登录成功且弹出音乐框
{
MessageBox.Show( "登录成功！");
userName.Text = "";
passWord.Text = "";
caozuoyemain frm = new caozuoyemain();
frm.ShowDialog();
}
else
{
MessageBox.Show("密码错误！"); //否则密码错误
userName.Text = "";
passWord.Text = "";
}
}
catch (Exception)
{
throw; //抛出异常
}
finally
{
Connection.Close(); //关闭数据库
}
}
private void label4_Click(object sender, EventArgs e)
{
zhuce fra = new zhuce();
fra.ShowDialog();
}
private void label6_Click(object sender, EventArgs e)
{
zhaohuimima fra = new zhaohuimima();
fra.ShowDialog();
}
private void denglu_Load(object sender, EventArgs e)
{
}
}
}
