登录界面连接数据库问题

Question

数据库界面c#密码

Answer 1

就是winform+ado.net，你多去看看winform和ado.net的基础吧，没有学会走，你就开始跑了

Answer 2

所谓“业务逻辑层”，对于你来说，其实就是（在这里就仅仅有）一个 public static bool 验证用户登录(string userName, string password)
{
    .....
}这样的代码。它把什么“界面”跟什么“数据库”隔离开来，省得你“两头找借口”。如果你只是关心数据库操作，那么你应该单独提出一个关于如何“访问关系数据库然后返回一个 bool 值来判断登录结果”的问题。应该自己先设计程序流程，不要一味地求别人给你把“所有功能”最终代码写出来。

Answer 3

http://sxfenglei.blog.163.com/blog/static/1702604912009184345826/

Answer 4

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 SelectCourse
{
    public partial class FrmInformation : Form
    {
        bool set = true;
        public FrmInformation()
        {
            InitializeComponent();
        }        private void FrmInformation_Load(object sender, EventArgs e)
        {
            try
            {
                string sqlStr = "select userName,name,answer1,answer2,answer3 from tbl_Information where userName='" + CPublic.userInfo[0] + "'";
                SqlCommand cmd = new SqlCommand(sqlStr, CDataBase.conn);
                CDataBase.conn.Open();
                SqlDataReader sdr = cmd.ExecuteReader();
                if (sdr.Read())
                {
                    txtName.Text = sdr["name"].ToString().Trim();
                    txtAnswer1.Text = sdr["answer1"].ToString().Trim();
                    txtAnswer2.Text = sdr["answer2"].ToString().Trim();
                    txtAnswer3.Text = sdr["answer3"].ToString().Trim();
                    set = false;
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            finally
            {
                CDataBase.conn.Close();
            }
        }        private void btnSetInformation_Click(object sender, EventArgs e)
        {
            try 
            {
                if(txtName.Text.Trim()=="")
                {
                    MessageBox.Show("姓名不能为空","提示");
                    txtName.Focus();
                    return;
                }
                else if(txtAnswer1.Text.Trim()=="")
                {
                    MessageBox.Show("请输入第一个问题的答案","提示");
                    txtAnswer1.Focus();
                    return;
                }
                else if(txtAnswer2.Text.Trim()=="")
                {
                    MessageBox.Show("请输入第二个问题的答案","提示");
                    txtAnswer2.Focus();
                    return;
                }
                else if(txtAnswer3.Text.Trim() =="")
                {
                    MessageBox.Show("请输入第三个问题的答案","提示");
                    txtAnswer3.Focus();
                    return;
                }
                string sqlStr;
                if(set)
                {
                    sqlStr = "insert into tbl_Information values('"+CPublic.userInfo[0] + "','"+txtName.Text.Trim()+"','"+txtAnswer1.Text.Trim()+"','"+txtAnswer2.Text.Trim()+"','"+txtAnswer3.Text.Trim()+"')";
                    if(CDataBase.UpdateDB(sqlStr))
                    {
                        MessageBox.Show("设置个人信息成功","恭喜");
                        set = false;
                        sqlStr = "update tbl_User set firstLogin='否' where userName='" + CPublic.userInfo[0] + "'";
                        CDataBase.UpdateDB(sqlStr);
                    }
                }
                else 
                {
                    sqlStr = "update tbl_Information set name= '"+txtName.Text.Trim()+"',Answer1='"+txtAnswer1.Text.Trim()+"',Answer2='"+txtAnswer2.Text.Trim()+"',Answer3='"+txtAnswer3.Text.Trim()+"'where userName='"+CPublic.userInfo[0]+"'";
                    if(CDataBase.UpdateDB(sqlStr))
                    {
                        MessageBox.Show("修改个人信息成功","恭喜");
                    }
                }
            }
                catch(Exception ex)
            {
                    CDataBase.conn.Close();
                    MessageBox.Show(ex.Message);
                }
        }        private void btnDeleteInformation_Click(object sender, EventArgs e)
        {
            try
            {
                if (MessageBox.Show("删除个人信息后，一旦忘记用户密码，将无法找回，确定删除吗？", "删除个人信息", MessageBoxButtons.YesNo, MessageBoxIcon.Warning, MessageBoxDefaultButton.Button2) == DialogResult.Yes)
                {
                    string sqlStr = "delete from tbl_Information where userName='" + CPublic.userInfo[0] + "'";
                    if (CDataBase.UpdateDB(sqlStr))
                    {
                        txtName.Text = "";
                        txtAnswer1.Text = "";
                        txtAnswer2.Text = "";
                        txtAnswer3.Text = "";
                        sqlStr = "update tbl_User set firstLogin='是' where userName='" + CPublic.userInfo[0] + "'";
                        CDataBase.UpdateDB(sqlStr);
                        MessageBox.Show("删除个人信息成功", "恭喜");
                        set = true;
                        txtName.Focus();
                    }
                }
            }
            catch (Exception ex)
            {
                CDataBase.conn.Close();
                MessageBox.Show(ex.Message);
            }
        }        private void btnChagePassword_Click(object sender, EventArgs e)
        {
            try
            {
                if (CPublic.GetMd5Str(txtOldPassword.Text.Trim()) != CPublic.userInfo[1])
                {
                    MessageBox.Show("旧密码错误，请重新输入", "提示");
                    txtOldPassword.Text = "";
                    txtNewPassword1.Text = "";
                    txtNewPassword2.Text = "";
                    txtOldPassword.Focus();
                }
                else if (txtNewPassword1.Text.Trim() == "" && txtNewPassword2.Text.Trim() == "")
                {
                    MessageBox.Show("密码不能为空", "提示");
                    txtNewPassword1.Focus();
                }
                else if (txtNewPassword1.Text.Trim() == txtNewPassword2.Text.Trim())
                {
                    string psw = CPublic.GetMd5Str(txtNewPassword1.Text.Trim());
                    string sqlStr = "update tbl_User set userPassword='" + psw.Trim() + "'where userName='" + CPublic.userInfo[0] + "'";
                    if (CDataBase.UpdateDB(sqlStr))
                    {
                        CPublic.userInfo[1] = psw.Trim();
                        MessageBox.Show("修改成功，请记住您的新密码", "修改密码");
                        txtOldPassword.Text = "";
                        txtNewPassword1.Text = "";
                        txtNewPassword2.Text = "";
                    }
                }
                else
                {
                    MessageBox.Show("两次输入的密码不一致", "提示");
                    txtNewPassword1.Text = "";
                    txtNewPassword2.Text = "";
                    txtNewPassword1.Focus();
                }
            }
            catch (Exception ex)
            {
                CDataBase.conn.Close();
                MessageBox.Show(ex.Message);
            }
        }        private void btnClose_Click(object sender, EventArgs e)
        {
            this.Close();
        }        private void txtNewPassword2_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter)
            {
                btnChagePassword_Click(sender, e);
            }
        }
    }
}

Answer 5

登陆界面连接数据库实现登陆示例
//登陆页面设置
<asp:TextBox ID="txtUid" runat="server" Font-Size="9pt" Width="120px" 
          BackColor="White"></asp:TextBox>//新用户登陆
<asp:TextBox ID="txtPwd" runat="server" Font-Size="9pt" TextMode="Password"
          Width="120px" style="margin-left: 0px" BackColor="White">
       </asp:TextBox>
 <asp:ImageButton ID="ImageManage" runat="server" ImageUrl="~/image/b1.jpg" 
                  OnClick="btnLoad_Click"/>//登陆按钮
//连接数据库实现登陆
 protected void btnLoad_Click(object sender, ImageClickEventArgs e)
    {
              DataSet ds = DB.reDs("select * from tb_HuenLian where UserName='" + txtUid.Text.Trim() + "' and PassWord='" + txtPwd.Text.Trim() + "'");
            int i = this.checkLogin(txtUid.Text, txtPwd.Text);
            if (i > 0)
            {
                Session["id"] = ds.Tables[0].Rows[0][0].ToString();
                Session["UserName"] = this.txtUid.Text;
                Session["PassWord"] = this.txtPwd.Text;
                Page.Response.Redirect("Yonghu.aspx");
            }
            else
            {
                Response.Write("<script lanuage=javascript>alert('用户名称或密码错误！');location='javascript:history.go(-1)'</script>");
            }//CodeGo.net/
    }
 public int checkLogin(string loginName, string loginPwd)//查询数据表用户名、密码是否正确
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.AppSettings["conn"]);
        SqlCommand myCommand = new SqlCommand("select count(*) from tb_HuenLian where UserName=@loginName and PassWord=@loginPwd", con);
        myCommand.Parameters.Add(new SqlParameter("@loginName", SqlDbType.NVarChar, 20));
        myCommand.Parameters["@loginName"].Value = loginName;
        myCommand.Parameters.Add(new SqlParameter("@loginPwd", SqlDbType.NVarChar, 50));
        myCommand.Parameters["@loginPwd"].Value = loginPwd;
        myCommand.Connection.Open();
        int i = (int)myCommand.ExecuteScalar();
        myCommand.Connection.Close();
        return i;
    }