Question

我想在用户登录后说出用户名（例如）“欢迎Bruce” 或者“欢迎蝙蝠侠”之类的东西。如何获取特定列的值并将其显示在消息框上？我正在使用visualt studio c＃2008和ms sql 2005.windows form

using (SqlConnection conn = new SqlConnection("Data Source=MJ-PC\\SQLEXPRESS;Initial Catalog=Users;Integrated Security=True"))
            {
                conn.Open();
                SqlCommand cmd = new SqlCommand("SELECT * FROM tblUsers WHERE U_Name=@U_Name AND U_Pass=@U_Pass", conn);
                cmd.Parameters.Add("@U_Name", SqlDbType.VarChar).Value = textBox1.Text;
                cmd.Parameters.Add("@U_Pass", SqlDbType.VarChar).Value = textBox2.Text;

                using (SqlDataReader dr = cmd.ExecuteReader())
                {




                    if (dr.HasRows)
                    {
                        dr.Read();
                        int userType = Convert.ToInt32(dr["U_Type"]);

                        if (userType == 1)
                        {
                            MessageBox.Show("Login Successful");
                            MDIParent1 settingsForm = new MDIParent1();
                            settingsForm.Show();
                            this.Hide();
                        }
                        else if (userType == 2)
                        {
                            MessageBox.Show("Login Successful");
                            MDIParent2 settingsForm = new MDIParent2();
                            settingsForm.Show();
                            this.Hide();
                        }
                    }


                    else
                    {
                        MessageBox.Show("Login Failed");
                        Outcome = Convert.ToInt32(lblOutcome.Text);
                        Outcome = Outcome - 1;
                        textBox1.Clear();
                        textBox2.Clear();

                        lblOutcome.Text = Outcome.ToString();
                        if (Outcome == 0)
                        {
                            MessageBox.Show("You have reached the maximum number of trial");
                            this.Close();
                        }
                    }

这是我的代码

在我的数据库中我有一个U_Name和F_Name，我想显示F_Name

Answer 1

您可以在登录成功时使用下面提到的代码。

MessageBox.Show("welcome "+textBox1.Text);

Answer 2

您已经可以访问数据（假设它在查询返回的同一行中），因此只需弹出另一个使用该值的MessageBox：

if (dr.HasRows)
{
    dr.Read();
    int userType = Convert.ToInt32(dr["U_Type"]);

    MessageBox.Show("Welcome, " + dr["F_Name"].ToString())

    if (userType == 1)
    {
        MessageBox.Show("Login Successful");
        MDIParent1 settingsForm = new MDIParent1();
        settingsForm.Show();
        this.Hide();
    }
    else if (userType == 2)
    {
        MessageBox.Show("Login Successful");
        MDIParent2 settingsForm = new MDIParent2();
        settingsForm.Show();
        this.Hide();
    }
}

Answer 3

您可以尝试：

Messagebox.Show(Context.User.Identity.Name.ToString());

如果您想要这样的用户名的一部分，可以使用拆分方法，

Context.User.Identity.Name.ToString().Split('\\')[1]

Answer 4

将用户名添加到公共静态字符串中。

将其用于所有子表单。

static class Program
{
   public static string sCurrentUserName;        

   /// <summary>
   /// The main entry point for the application.
   /// </summary>
   [STAThread]
   static void Main()
   {            
       Application.EnableVisualStyles();
       Application.SetCompatibleTextRenderingDefault(false);
       Application.Run(new Form1());
    }
}

在你的方法中：

 if (dr.HasRows)
 {
       dr.Read();
       int userType = Convert.ToInt32(dr["U_Type"]);

       if (userType == 1)
       {
           MessageBox.Show("Login Successful");
           MDIParent1 settingsForm = new MDIParent1();
           settingsForm.Show();
           this.Hide();
       }
       else if (userType == 2)
       {
           MessageBox.Show("Login Successful");
           MDIParent2 settingsForm = new MDIParent2();
           settingsForm.Show();
           this.Hide();
       } 
       Program.sCurrentUserName = dr["F_Name"].ToString(); 
  }
  else
  {
        Program.sCurrentUserName = string.Empty;
        //other code
  }

如何在子表单中使用：

public partial class Form2: Form
{       
    public Form2()
    { 
    }

    private void Form2_Load(object sender, EventArgs e)
    {
         if(string.IsNullOrEmpty(Program.sCurrentUserName) == false)
           MessageBox.Show("Welcome " + Program.sCurrentUserName);
         else
         {
             //do something
         }
    }
}

如何在c＃的消息框中显示用户名？

4 个答案: