Question

我是C＃的新手，目前正在使用“帐户” Windows应用程序。我没有使用ASP.NET，仅使用Winforms和.mdf数据库。我现在的主要目标是在登录后立即在主页上显示用户的详细信息（来自数据库）。

例如：

登录页面

用户名：sandy@mail.com

密码：1234

主页

欢迎，桑迪·史密斯！

您当前的地址：Woodlands Drive

这是我的“登录”按钮的代码：

    private void button1_Click(object sender, EventArgs e)
    {
        SqlConnection conn = new SqlConnection(@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=C:\Users\sit\Desktop\25June_LessonEffectivenessAnalysis\LessonEffectivenessAnalysis\LessonEffectivenessAnalysis\LessonEffectivenessAnalysis\LessonAnalysis.mdf;Integrated Security=True");
        SqlDataAdapter sda = new SqlDataAdapter("select count(*) from TBL_LOGIN where STAFF_EMAIL ='" + textBox1.Text + "' and PASSWORD='" + textBox2.Text + "'", conn);
        DataTable dt = new DataTable();
        sda.Fill(dt);
        if (dt.Rows[0][0].ToString() == "1")
        {
            this.Hide();
            Home_Page hp = new Home_Page();
            hp.Show();
        }
        else
        {
            MessageBox.Show("Please a valid email and password.", "alert", MessageBoxButtons.OK, MessageBoxIcon.Error);
        }
    }

如果有人可以帮助，将不胜感激。谢谢！

Answer 1

这就是我使用winforms

的方式

在数据库创建表USERS中，其列为USERID，PASS，DISPLAY_NAME，EMAIL，ANYTHING YOU WANT TO STORE FOR EACH USER ......

创建新类（.cs file）并将其命名为CurrentUser

在其中为数据库中的每一列创建public static vars-可以从代码中的任何位置（写/读）访问的数据类型。

所以类看起来像这样：

public class CurrentUser
{
    public static int userId;
    public static string pass;
    public static string displayName;
    public static string email;
    //every other column you added
}

现在创建这样的登录代码

private void button1_Click(object sender, EventArgs e)
{
    using(SqlConnection conn = new SqlConnection(@"Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=C:\Users\sit\Desktop\25June_LessonEffectivenessAnalysis\LessonEffectivenessAnalysis\LessonEffectivenessAnalysis\LessonEffectivenessAnalysis\LessonAnalysis.mdf;Integrated Security=True");
    {
        conn.Open();
        using(SqlCommand cmd = new SqlCommand("SELECT PASS, USERID, DISPLAY_NAME, FROM USERS WHERE EMAIL = @MAIL", conn)
        {
            cmd.Parameters.AddWithValue("@MAIL", textBox1.Text);

            SqlDataReader dr = cmd.ExecuteReader():

            if(dr.Read()) //We do IF since we only need first one
            {
                //Now we check if typed password is equal to password from database
                if(dr[0].ToString().Equals(textBox2.Text))
                {
                    this.Hide();
                    Home_Page hp = new Home_Page();
                    hp.Show();


                    //Here we store current user data
                    CurrentUser.userId = Convert.ToInt32(dr[1]);
                    CurrentUser.pass = dr[0].ToString();
                    CurrentUser.displayName = dr[2].ToString();
                    CurrentUser.email = textBox1.Text;
                }
                else //Passwords doesn't match
                {
                    MessageBox.Show("Wrong password. Try again");
                }
            }
            else //If it hasn't found anyone with that email that mean email is incorect
            {
                MessageBox.Show("E-mail doesn't exist!");
            }
        }
    }
}

现在，无论您属于哪种类/形式（位于名称空间中），都可以使用string displayName = CurrentUser.displayName访问当前用户的数据。

或者如果您想设置带有问候消息的标签，则可以

label1.Text = "Welcome, " + CurrentUser.displayName + "!";

更好

label1.Text = String.Format("Welcome, {0}!", CurrentUser.displayName);

或者，如果您想显示包含所有数据的messageBox，请这样做

string[] msg = {
String.Format("Welcome, {0}.", CurrentUser.displayName),
String.Format("Your ID is: {0} while your e-mail is {1}!", CurrentUser.userId, CurrentUser.email)
};

MessageBox.Show(String.Joing(Environment.NewLine, msg));

是否可以在没有ASP.NET的情况下创建“用户帐户” Windows应用程序？

1 个答案: