Question

我正在尝试创建一个登录页面，并针对数据库验证传入的详细信息。但是我的代码无法交叉检查数据库中的数据。下面是我从应用程序中获得的输出结果：

以下是我正在处理的代码

Default.aspx代码：

<%@ Page Title="" Language="C#" MasterPageFile="~/MasterPage.master"AutoEventWireup="true" CodeFile="LogIn.aspx.cs" Inherits="LogIn" %>

<asp:Content ID="Content1" ContentPlaceHolderID="Head" Runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="body" Runat="Server">
<!-- Login & Register -->
    <section>
    <div class="pageintro">
        <div class="pageintro-bg">
            <img src="images/bg-page_01.jpg" alt="About Us"/>
        </div>
        <div class="pageintro-body">
            <h1 class="pageintro-title">Login</h1>
            <nav class="pageintro-breadcumb">
                <ul>
                    <li>
                        <a href="#">Home</a>
                    </li>
                    <li>
                        <a href="#">Login</a>
                    </li>
                </ul>
            </nav>
        </div>
    </div>
</section>

            <!-- Login -->
            <div class="col-lg-6 ">
                <div class="au-form-body p-r-lg-15 p-r-xl-15">
                    <h2 class="au-form-title form-title-border">Login</h2>
                    <fieldset class="m-t-40">

                            <div class="form-group au-form require">
                                <label>Email address</label>
                                 <asp:TextBox ID="txtemail" runat="server"></asp:TextBox>
                            </div>
                            <div class="form-group au-form require">
                                <label>Password</label>
                                 <asp:TextBox ID="txtpwd" runat="server" TextMode="Password"></asp:TextBox>
                            </div>
                            <div class="form-group au-form">
                                <asp:Button ID="loginbtn" runat="server" Text="Log In" OnClick="Button1_Click" />
                                <asp:Label ID="loginmessage" runat="server"></asp:Label>
                                <asp:Button ID="logoutbtn" runat="server" OnClick="Button2_Click" Text="Log Out" Visible="False" />
                                <div class="form-forgot w-100 m-t-10">
                                    <a href="forgetpassword.aspx">Lost your password?</a>
                                </div>
                            </div>

                    </fieldset>
                </div>
            </div>
            <!-- End Login -->

Default.aspx.cs代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.SqlClient;

public partial class LogIn : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{


}
protected void Button1_Click(object sender, EventArgs e)
{
    SqlConnection sqlCon = new SqlConnection(@"Data Source=TEAFAMILY;Initial Catalog=Bolsen;Integrated Security=True; MultipleActiveResultSets=true;");
    sqlCon.Open();
    Type cstype = this.GetType();
    SqlCommand cmd;
    SqlDataReader rdr;
    String strSql1 = "SELECT * FROM Customers ";
    cmd = new SqlCommand(strSql1, sqlCon);
    rdr = cmd.ExecuteReader();

    while (rdr.Read() == true)
    {
        if (txtemail.Text == (string)rdr["cEmail"] &&
            txtpwd.Text == (string)rdr["cPassword"])
        {
            Session["sFlag"] = "T"; // sFlag = "T" means user has logged in
            Session["sName"] = rdr["Firstname"];
            Session["sEmail"] = rdr["cEmail"];
            Session["sAddress"] = rdr["cCompanyAddress"];
            Session["sEmail"] = rdr["cEmail"];
            logoutbtn.Visible = true;
            sqlCon.Close();
            Response.Redirect("Default.aspx");
        } //end of if
    } //end of while loop
    // userid and password not matched, hence login unsuccessful
    Session["sFlag"] = "F";
    Session["sName"] = "";
    Session["sUserId"] = "";
    loginmessage.Text = "Error in login - Please login again   ";

    sqlCon.Close();
}
protected void Button2_Click(object sender, EventArgs e)
{
    logoutbtn.Visible = false;
    Session["sFlag"] = "L"; // L for logout
    Session["sName"] = "";
    Session["sUserId"] = "";
    Session["sOrderNo"] = "";
    txtemail.Text = "";
    txtpwd.Text = "";
    Response.Redirect("Default.aspx");

}
}

有人会指出代码有什么问题吗？

Answer 1

无需仅从数据库中获取所有记录即可检查单个结果。将您的Button1_Click事件代码更改为此：

    protected void Button1_Click(object sender, EventArgs e)
    {
        string username = txtemail.Text;
        string password = txtpwd.Text;
        using (SqlConnection sqlCon = new SqlConnection(@"Data Source=TEAFAMILY;Initial Catalog=Bolsen;Integrated Security=True; MultipleActiveResultSets=true;"))
        {
            string query = "SELECT Top(1) * FROM Customers WHERE cEmail = @Username and cPassword = @Password";
            SqlCommand cmd = new SqlCommand(query, sqlCon);
            cmd.Parameters.AddWithValue("@Username", username);
            cmd.Parameters.AddWithValue("@Password", password);
            sqlCon.Open();

            SqlDataReader rdr = cmd.ExecuteReader();
            if (rdr.Read())
            {
                Session["sFlag"] = "T"; // sFlag = "T" means user has logged in
                Session["sName"] = rdr["Firstname"];
                Session["sEmail"] = rdr["cEmail"];
                Session["sAddress"] = rdr["cCompanyAddress"];
                Session["sEmail"] = rdr["cEmail"];
                logoutbtn.Visible = true;
                sqlCon.Close();
                Response.Redirect("Default.aspx");
            }
            else
            {
                Session["sFlag"] = "F";
                Session["sName"] = "";
                Session["sUserId"] = "";
                loginmessage.Text = "Error in login - Please login again   ";
            }
        }
    }

如何从数据库中提取信息？

1 个答案: