用户尝试使用计数

Question

我想使用条件在我的计数中创建用户尝试。我如何使用条件来执行这种逻辑以及在下面的代码中放置的位置。示例：如果用户尝试登录 3 次，但用户输入错误并通过，他将收到一条消息，提示您已达到登录尝试次数private void btn_login_Click(object sender, EventArgs e){        var obj = new Usercontrols.SIMSMain();        obj.Dock = DockStyle.Fill;        conn.Open();        SqlCommand selectCommand = new SqlCommand("Select * from admin_access where Username=@admin AND Password=@eyelab",conn);        selectCommand.Parameters.AddWithValue("@admin", txt_username.Text);        selectCommand.Parameters.AddWithValue("@eyelab", txt_password.Text);        SqlDataReader dataReader;           dataReader = selectCommand.ExecuteReader();        var count = 0;        while (dataReader.Read())        {            count = count + 1;        }    if (string.IsNullOrEmpty(txt_username.Text) || string.IsNullOrEmpty(txt_password.Text))    {        MetroMessageBox.Show(this, "Please input the Required Fields", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);    }    else    {        if (count == 1)        {            MetroMessageBox.Show(this, "Login Successful", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Information);            this.Hide();            this.Parent.Controls.Add(obj);        }        else if (count == 3)        {            count++;            MetroMessageBox.Show(this, "Super Attempt", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Information);        }        else        {            MetroMessageBox.Show(this, "Invalid Username/Password", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Stop);        }        }    conn.Close();}

Answer 1

这是您修改后的代码，用于处理超过 3 次的尝试

Timer loginAttempsTimeOut;

Dictionary<string, int> loginAttempsPerUser = new Dictionary<string,int>();

Dictionary<string, DateTime> loginAttemptsViolated = new Dictionary<string, DateTime>();

int TimeOutInMinutes = 15;

private void SetTimer()

{

    loginAttempsTimeOut = new Timer();

    loginAttempsTimeOut.Interval = 1000 * 60; // check timeout every 1 mins

    loginAttempsTimeOut.Enalbed = true;

    loginAttempsTimeOut.Tick += LoginAttempsTimeOut_Tick;

}

// set a timer, and if login timeout for each user is elapsed,

// allow user to try login again

private void LoginAttempsTimeOut_Tick(object sender, EventArgs e)

{

    foreach(var user in loginAttemptsViolated.Keys)

    {

        loginAttemptsViolated.TryGetValue(user, out var date);

        TimeSpan span = DateTime.Now.Subtract(date);

        if(span.TotalMinutes > TimeOutInMinutes)

        {

            loginAttempsPerUser[user] = 0;

            loginAttemptsViolated.Remove(user);

            loginAttempsPerUser.Remove(user); 

        }

    }

}

private void btn_login_Click(object sender, EventArgs e)

{

        var obj = new Usercontrols.SIMSMain();

        obj.Dock = DockStyle.Fill;

        conn.Open();

        SqlCommand selectCommand = new SqlCommand("Select * from admin_access where Username=@admin AND Password=@eyelab", conn);

        selectCommand.Parameters.AddWithValue("@admin", txt_username.Text);

        selectCommand.Parameters.AddWithValue("@eyelab", txt_password.Text);

        SqlDataReader dataReader;

        dataReader = selectCommand.ExecuteReader();

        var count = 0;

        while (dataReader.Read())

        {

            count = count + 1;

        }

        if(loginAttemptsViolated.ContainsKey(txt_username.Text))

        {

           MetroMessageBox.Show("Login attempts is more than 3.");

        }

        else if (string.IsNullOrEmpty(txt_username.Text) || string.IsNullOrEmpty(txt_password.Text))

        {

            MetroMessageBox.Show(this, "Please input the Required Fields", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

        }

        else

        {

            if (count == 1)

            {

                MetroMessageBox.Show(this, "Login Successful", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Information);

                this.Hide();

                this.Parent.Controls.Add(obj);

            }

            else if (count == 3)

            {

                count++;

                MetroMessageBox.Show(this, "Super Attempt", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Information);

            }

            else

            {

                //if user cannot login, increase login attempts

                if(!loginAttempsPerUser.ContainsKey(txt_username.Text))

                   loginAttempsPerUser.Add(txt_username.Text, 1);

                loginAttempsPerUser[txt_username.Text]++;

                if(loginAttempsPerUser[txt_username.Text] > 2)

                {

                    // if login attempts > 2 set a 15 min timeout till user 

                    // cant login

                    if(!loginAttemptsViolated.ContainsKey(txt_username.Text))

                       loginAttemptsViolated.Add(txt_username.Text, DateTime.Now);

                }

                MetroMessageBox.Show(this, "Invalid Username/Password", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Stop);

            }

        }

        conn.Close();

    }

}

也有超时，因为如果用户违反了登录计数，则必须稍后再给他/她一次机会（例如 15 分钟后）。

Answer 2

您需要将计数变量声明为全局变量。

    int count = 1;

    private void btn_login_Click(object sender, EventArgs e)

    {

        var obj = new Usercontrols.SIMSMain();

        obj.Dock = DockStyle.Fill;

        conn.Open();

        SqlCommand selectCommand = new SqlCommand("Select * from admin_access where Username=@admin AND Password=@eyelab", conn);

        selectCommand.Parameters.AddWithValue("@admin", txt_username.Text);

        selectCommand.Parameters.AddWithValue("@eyelab", txt_password.Text);

        SqlDataReader dataReader;

        dataReader = selectCommand.ExecuteReader();

        var counter = 0; //to check if there is data

        while (dataReader.Read())

        {

            counter++;

        }

        if (string.IsNullOrEmpty(txt_username.Text) || string.IsNullOrEmpty(txt_password.Text))

        {

            MetroMessageBox.Show(this, "Please input the Required Fields", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

        }

        else

        {

            if (counter == 1)

            {

                MetroMessageBox.Show(this, "Login Successful", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Information);

                this.Hide();

                this.Parent.Controls.Add(obj);

            }

            else if (count == 3)

            {

                count++;

                MetroMessageBox.Show(this, "Super Attempt", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Information);

            }

            else

            {

                count++;

                MetroMessageBox.Show(this, "Invalid Username/Password", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Stop);

            }

        }

        conn.Close();

    }

Answer 3

您已经在使用SqlDataReader.Read()简单的 else 可以处理没有结果返回的情况。您已经在使用SqlDataReader.Read()简单的 else 可以处理没有结果返回的情况。

int failAttempt  = 0;

private void btn_login_Click(object sender, EventArgs e)

{

    // Step 1: Check if inputs are valid

    if (string.IsNullOrEmpty(txt_username.Text) || string.IsNullOrEmpty(txt_password.Text))

    {

        MetroMessageBox.Show(this, "Please input the Required Fields", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);

        return;

    }

    // Step 2: Check if there is one user with this password/login

    var obj = new Usercontrols.SIMSMain();

    obj.Dock = DockStyle.Fill;

    conn.Open();

    SqlCommand selectCommand = new SqlCommand("Select * from admin_access where Username=@admin AND Password=@eyelab",conn);

    selectCommand.Parameters.AddWithValue("@admin", txt_username.Text);

    selectCommand.Parameters.AddWithValue("@eyelab", txt_password.Text);

    SqlDataReader dataReader = selectCommand.ExecuteReader();

    int numberMatch=0;

    while(dataReader.Read()){

        numberMatch++;

    }

    conn.Close();

    // Step 3: Fail Handle

    if(numberMatch==1){ // Success

        failAttempt  = 0;

        MetroMessageBox.Show(this, "Login Successful", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Information);

        this.Hide();

        this.Parent.Controls.Add(obj);

    }

    else { // Fail 0 or more than one

        failAttempt ++;

        if (failAttempt == 3)

        {

            MetroMessageBox.Show(this, "Super Attempt", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Information);

        }

        else

        {

            MetroMessageBox.Show(this, "Invalid Username/Password", "System Message:", MessageBoxButtons.OK, MessageBoxIcon.Stop);

        }

    }