ASP.NET菜鸟之路之登录系统

背景

我是一个ASP.NET菜鸟，暂时开始学习ASP.NET，在此记录下我个人敲的代码，没有多少参考价值，请看到的盆友们为我点个赞支持我一下，多谢了。

网站介绍

根据书上的例子做了一个比较粗糙的登录例子，里面的代码都是自己敲出来的，而且很少使用封装方法，就是为了让自己能更清楚的记住做的过程。

这个网站包含注册、登录、修改密码三个功能。

注册介绍

新建一个Web窗体，即UserManagers.aspx。不粘贴前台代码了。然后编写注册方法，包括用户名当作主键，SqlDataReader方式读取数据库，SqlCommand参数添加数据等要点

protected void Button1_Click(object sender, EventArgs e)
    {
        if (txtName.Text == "" || txtPwd.Text == "" || txtConfirm.Text == "")
        {
            this.Page.RegisterStartupScript("ss", "<script>alert('用户名密码不能为空')</script>");
            return;
        }

        if (txtPwd.Text.Equals(txtConfirm.Text))
        {
            //查看当前用户是否存在
            SqlConnection sqlConn = new SqlConnection(ConfigurationManager.ConnectionStrings["connection"].ConnectionString);
            sqlConn.Open();
            string sql = "select * from tb_user where username = '" + txtName.Text.Trim() + "'";
            SqlCommand sqlCommand = new SqlCommand(sql, sqlConn);
            SqlDataReader sqlDataReader = sqlCommand.ExecuteReader();
            if (sqlDataReader.Read())
            {
                Page.RegisterStartupScript("", "<script>alert('用户名已存在！')</script>");
                return; 
            }
            sqlDataReader.Close();

            //新增用户
            string strInsert = "insert into tb_user(username, pwd, marks) values (@username,@pwd, @marks)";
            sqlCommand = new SqlCommand(strInsert, sqlConn);
            sqlCommand.Parameters.Add("@username", SqlDbType.VarChar);
            sqlCommand.Parameters["@username"].Value = txtName.Text;

            sqlCommand.Parameters.Add("@pwd", SqlDbType.VarChar, 20);
            sqlCommand.Parameters["@pwd"].Value = txtPwd.Text;

            sqlCommand.Parameters.Add("@marks", SqlDbType.VarChar, 1000);
            sqlCommand.Parameters["@marks"].Value = "zbq测试";

            sqlCommand.ExecuteNonQuery();
            sqlConn.Close();

            Page.RegisterStartupScript("", "<script>alert('注册成功！')</script>");
            Response.Redirect("Default.aspx?Name=" + txtName.Text + "");
        }
    }

界面效果如下

登录介绍

首先添加登录窗口ManageLogin.aspx，然后写登录代码，包含验证码这一要点

protected void btnLogin_Click(object sender, EventArgs e)
    {
        if (string.IsNullOrEmpty(txtName.Text)|| string.IsNullOrEmpty(txtPwd.Text) || string.IsNullOrEmpty(txtValid.Text))
        {
            Page.RegisterStartupScript("", "<script>alert('信息填写不完全！')</script>");
            return;
        }
        if (!txtValid.Text.ToUpper().Equals(Session["ValidNums"]))
        {
            Page.RegisterStartupScript("", "<script>alert('验证码不正确！')</script>");
            return;
        }

        SqlConnection sql = new SqlConnection(ConfigurationManager.ConnectionStrings["connection"].ConnectionString);
        sql.Open();

        string select = "select * from tb_user t where t.username = '" + txtName.Text.Trim() + "' and pwd = '" + txtPwd.Text.Trim() +
                        "'";

        SqlCommand command = new SqlCommand(select, sql);

        SqlDataReader dataReader = command.ExecuteReader();

        if (dataReader.Read())
        {
            //成功就跳转
            Response.Redirect("Default.aspx?Name=" + txtName.Text + "");
        }
        else
        {
            Page.RegisterStartupScript("", "<script>alert('账户名或密码错误！')</script>");
            dataReader.Close();
            return;
        }

登录效果如图

  

修改密码介绍

首先建立一个EditPwd.aspx窗体

<table class="table" border="1px" align="center">
                <tr>
                    <td class="firstTd">用户名：</td>
                    <td >
                        <asp:DropDownList runat="server" ID="names" Width="200px" Height="20px" />
                    </td>
                </tr>
                <tr>
                    <td class="firstTd">原密码：</td>
                    <td >
                        <asp:TextBox runat="server" ID="txtOldPwd" TextMode="Password" />
                    </td>
                </tr>
                <tr>
                    <td class="firstTd">新密码：</td>
                    <td >
                        <asp:TextBox runat="server" ID="txtNewPwd" TextMode="Password"></asp:TextBox>
                    </td>
                </tr>
                <tr>
                    <td class="firstTd">&nbsp;</td>
                    <td align="right">
                        <span >
                            <asp:Button runat="server"  ID="btnSure" OnClick="btnSure_Click" Text="确认登录"/>
                            <asp:Button runat="server"  ID="btnCancle" OnClick="btnCancle_Click" Text="取消"/>    
                        </span>
                    </td>
                </tr>
                
            </table>

然后编写修改方法，包含SqlDataAdapter + DataSet关键点

protected void Page_Load(object sender, EventArgs e)
    {
       //初始化数据
        if (!IsPostBack)
        {
            SqlConnection sql = new SqlConnection(ConfigurationManager.ConnectionStrings["connection"].ConnectionString);
            sql.Open();
            string select = "select * from tb_user";
            SqlDataAdapter sqlDataAdapter = new SqlDataAdapter(select, sql);

            DataSet dataSet = new DataSet();
            sqlDataAdapter.Fill(dataSet);
            sql.Close();
            if (dataSet.Tables[0].Rows.Count> 0)
            {
                for (int index = 0; index < dataSet.Tables[0].Rows.Count; index++)
                {
                    names.Items.Add(dataSet.Tables[0].Rows[index][1].ToString());

                }
            }
        }
    }
    protected void btnSure_Click(object sender, EventArgs e)
    {

        if (string.IsNullOrEmpty(txtNewPwd.Text) || string.IsNullOrEmpty(txtOldPwd.Text))
        {
            Page.RegisterStartupScript("", "<script>alert('密码不能为空或者不能不相等！')</script>");
            return;
        }

        SqlConnection sqlConnection = new SqlConnection("server=PC-20150424DMHQ;database=MyDatas;uid=sa;pwd=123456");
        string select = "select * from tb_user where username = '" +names.Text + "'";
        SqlCommand sqlCommand = new SqlCommand(select, sqlConnection);
        sqlConnection.Open();
        SqlDataReader sqlDataReader = sqlCommand.ExecuteReader();
        if (sqlDataReader.Read())
        {
            if (sqlDataReader["pwd"].ToString() != txtOldPwd.Text)
            {
                Page.RegisterStartupScript("", "<script>alert('密码输入错误！')</script>");
                return;
            }
        }
        else
        {
            Page.RegisterStartupScript("", "<script>alert('数据库连接错误！')</script>");
            return;
        }
        sqlConnection.Close();
        sqlDataReader.Close();

        
        //修改密码
        sqlConnection.Open();
        string updatePwd = "update tb_user set pwd = '" + txtNewPwd.Text + "' where username = '" + names.Text + "'";
        sqlCommand = new SqlCommand(updatePwd, sqlConnection);

        sqlCommand.ExecuteNonQuery();
        sqlConnection.Close();
        Page.RegisterStartupScript("", "<script>alert('修改成功！')</script>");
        Page_Load(null, null);
    }

修改密码界面效果