C#连接数据库实现登录注册界面

开发环境

OS：Windows 7 64位

IDE：Microsoft VisualStudio 2010

数据库：SQL Server 2008 R2

最终效果

 

 

数据库

 

代码

Login.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;

namespace Login
{
    public partial class Login : Form
    {
        public Login()
        {
            InitializeComponent();
        }

        private void loginBtn_Click(object sender, EventArgs e)
        {
            string uername = name.Text.Trim();
            string pwd = password.Text;
            string constr = "Server=.;DataBase=Management;Integrated Security=True";
            // 建立SqlConnection对象
            SqlConnection con = new SqlConnection(constr);
            // 打开连接
            con.Open();
            // 指定SQL语句
            SqlCommand com = new SqlCommand("select account,password from register where account='" + uername + "' and password='" + pwd + "'", con);
            // 建立SqlDataAdapter和DataSet对象
            SqlDataAdapter da = new SqlDataAdapter(com);
            DataSet ds = new DataSet();

            int n = da.Fill(ds, "register");
            if (n != 0)
            {
                MessageBox.Show("登录成功！", "提示");
                label_title.Visible = false;
                label_userName.Visible = false;
                label_userPwd.Visible = false;
                name.Visible = false;
                password.Visible = false;
                button_reg.Visible = false;
                loginBtn.Visible = false;
            }
            else
            {
                MessageBox.Show("用户名或密码错误，请重新输入！", "提示");
                name.Text = "";
                password.Text = "";
                name.Focus();
            }
            con.Close();
        }

        private void button_reg_Click(object sender, EventArgs e)
        {
            Register reg = new Register();
            reg.ShowDialog();
        }

        private void Login_Load(object sender, EventArgs e)
        {

        }

        private void InitializeComponent()
        {
            this.name = new System.Windows.Forms.TextBox();
            this.password = new System.Windows.Forms.TextBox();
            this.loginBtn = new System.Windows.Forms.Button();
            this.button_reg = new System.Windows.Forms.Button();
            this.label_userName = new System.Windows.Forms.Label();
            this.label_userPwd = new System.Windows.Forms.Label();
            this.label_title = new System.Windows.Forms.Label();
            this.SuspendLayout();
            // 
            // name
            // 
            this.name.Location = new System.Drawing.Point(115, 89);
            this.name.Name = "name";
            this.name.Size = new System.Drawing.Size(174, 23);
            this.name.TabIndex = 0;
            // 
            // password
            // 
            this.password.Location = new System.Drawing.Point(115, 130);
            this.password.Name = "password";
            this.password.PasswordChar = '*';
            this.password.Size = new System.Drawing.Size(174, 23);
            this.password.TabIndex = 1;
            // 
            // loginBtn
            // 
            this.loginBtn.BackColor = System.Drawing.SystemColors.Menu;
            this.loginBtn.Location = new System.Drawing.Point(45, 186);
            this.loginBtn.Name = "loginBtn";
            this.loginBtn.Size = new System.Drawing.Size(335, 40);
            this.loginBtn.TabIndex = 2;
            this.loginBtn.Text = "登  录";
            this.loginBtn.UseVisualStyleBackColor = false;
            this.loginBtn.Click += new System.EventHandler(this.loginBtn_Click);
            // 
            // button_reg
            // 
            this.button_reg.BackColor = System.Drawing.SystemColors.Menu;
            this.button_reg.Location = new System.Drawing.Point(299, 86);
            this.button_reg.Name = "button_reg";
            this.button_reg.Size = new System.Drawing.Size(81, 27);
            this.button_reg.TabIndex = 3;
            this.button_reg.Text = "注  册";
            this.button_reg.UseVisualStyleBackColor = false;
            this.button_reg.Click += new System.EventHandler(this.button_reg_Click);
            // 
            // label_userName
            // 
            this.label_userName.AutoSize = true;
            this.label_userName.Location = new System.Drawing.Point(46, 92);
            this.label_userName.Name = "label_userName";
            this.label_userName.Size = new System.Drawing.Size(63, 14);
            this.label_userName.TabIndex = 4;
            this.label_userName.Text = "用 户 名";
            // 
            // label_userPwd
            // 
            this.label_userPwd.AutoSize = true;
            this.label_userPwd.Location = new System.Drawing.Point(46, 133);
            this.label_userPwd.Name = "label_userPwd";
            this.label_userPwd.Size = new System.Drawing.Size(63, 14);
            this.label_userPwd.TabIndex = 5;
            this.label_userPwd.Text = "密    码";
            // 
            // label_title
            // 
            this.label_title.AutoSize = true;
            this.label_title.Font = new System.Drawing.Font("微软雅黑", 18F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(134)));
            this.label_title.Location = new System.Drawing.Point(66, 21);
            this.label_title.Name = "label_title";
            this.label_title.Size = new System.Drawing.Size(292, 31);
            this.label_title.TabIndex = 6;
            this.label_title.Text = "欢 迎 使 用 XX 管 理 系 统";
            // 
            // Login
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(7F, 14F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.BackColor = System.Drawing.SystemColors.GradientInactiveCaption;
            this.ClientSize = new System.Drawing.Size(424, 262);
            this.Controls.Add(this.label_title);
            this.Controls.Add(this.label_userPwd);
            this.Controls.Add(this.label_userName);
            this.Controls.Add(this.button_reg);
            this.Controls.Add(this.loginBtn);
            this.Controls.Add(this.password);
            this.Controls.Add(this.name);
            this.Font = new System.Drawing.Font("宋体", 10.5F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(134)));
            this.Name = "Login";
            this.Text = "XX 管理系统";
            this.Load += new System.EventHandler(this.Login_Load);
            this.ResumeLayout(false);
            this.PerformLayout();

        }
    }
}

 

Register.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;

namespace Login
{
    public partial class Register : Form
    {
        public Register()
        {
            InitializeComponent();
        }

        private void button_reg_Click(object sender, EventArgs e)
        {
            string name = userName.Text.Trim();

            string constr = "Server=.;DataBase=Management;Integrated Security=True";
            // 建立SqlConnection对象
            SqlConnection con = new SqlConnection(constr);
            // 打开连接
            con.Open();
            // 指定SQL语句
            SqlCommand com = new SqlCommand("select account from register where account='" + name + "'", con);
            // 建立SqlDataAdapter和DataSet对象
            SqlDataAdapter da = new SqlDataAdapter(com);
            DataSet ds = new DataSet();

            int n = da.Fill(ds, "register");
            if (n != 0)
            {
                MessageBox.Show("用户名已存在！", "提示");
                userName.Text = "";
                userPwd.Text = "";
                userPwdCheck.Text = "";
            }
            else if (userName.TextLength > 16)
            {
                MessageBox.Show("用户名太长，我怕你记不住，请换个短的吧！", "提示");
            }
            else if (userPwd.Text != userPwdCheck.Text)
            {
                MessageBox.Show("两次输入的密码不一致！", "提示");
                userPwd.Text = "";
                userPwdCheck.Text = "";
            }
            else if (userName.Text == "" || userPwd.Text == "")
            {
                MessageBox.Show("用户名或密码不能为空！", "提示");
            }
            else if (userPwd.TextLength < 6 || userPwd.TextLength > 12)
            {
                MessageBox.Show("密码长度不符合要求！", "提示");
                userPwd.Text = "";
                userPwdCheck.Text = "";
            }
            else
            {
                // 指定SQL语句
                com = new SqlCommand("insert into register(account,password) values ('"
                    + userName.Text + "','" + userPwd.Text + "')", con);
                // 建立SqlDataAdapter和DataSet对象
                com.ExecuteNonQuery();
                com = null;
                MessageBox.Show("注册成功！", "提示");
                this.Close();
            }
            con.Close();
        }

        private void Register_Load(object sender, EventArgs e)
        {

        }
    }
}