ASP.NET菜鸟之路之登录系统

背景

注册介绍

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

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;  } 

  

修改密码介绍

<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"> </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