将Delphi作为ASP.NET的脚本语言

2022-07-15 80酷酷网 80kuku.com

　　asp.net|脚本

   将Delphi视为脚本语言

   支持ASP.net的第一件事是让ASP.NET将Delphi视为脚本语言，让ASP.NET能够为各种ASP文件类型调用Delphi的.NET编译器。

   ASP.NET要在IIS虚路径的根目录下寻找Web.config文件。下面是ASP.NET中使用Delphi作脚本语言的web.config配制文件内容：

   <configuration>
   <system.web>
   <compilation debug="true">
   <assemblies>
   <add assembly="DelphiProvider" />
   </assemblies>
   <compilers>
   <compiler language="Delphi" extension=".pas"
   type="Borland.Delphi.DelphiCodeProvider,DelphiProvider" />
   </compilers>
   </compilation>
   </system.web>
   </configuration>

   关于web配制文件的详情请参MSDN：
   http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguide/html/cpconformatofconfigurationfiles.asp

   在我的机器(Win2K Pro)上测试Delphi对ASP.NET的支持。要增加一个虚路径来安放Delphi脚本，我把这个路径名定为"vslive"。

   在我的机器配制文件上作了这个小改动后就可以来看ASP.NET是如何将Delphi视为脚本语言的。

   在ASP.NET中使用Delphi代码
   首先编写一个简单应用来确认我们的Delphi支持配制是正确的。下面是editdemo.aspx文件的代码，有一个文本输入框，一个按钮。按钮事件触发显示输入框内容。

   <html>
   <script language="Delphi" runat="server">
   procedure ButtonClick(Sender: System.Object; E: EventArgs);
   begin
   Message.Text := Edit1.Text;
   end;
   </script>
   <body>
   <form runat="server">
   <asp:textbox id="Edit1" runat="server"/>
   <asp:button text="Click Me!" runat="server"/>
   </form>
   <p><b><asp:label id="Message" runat="server"/></b></p>
   </body>
   </html>

   可以看到，ASP按钮对象的OnClick事件触发Delphi的ButtonClick过程，而Delphi程序里却使用了ASP对象label Message和text box Edit1。虽然在Delphi过程中没有定义ASP的二个变量，Delphi代码却能找到它们。这是因为脚本中含有的Delphi服务模块能够产生相应的Delphi代码。

   现在可以用本地浏览器来浏览这个网页了。因为我把脚本放在"vslive"虚路径，所以打开：
   http://localhost/vslive/editdemo.aspx.

   以下是编译之后形成的Delphi代码，代码产生WebForm：

//------------------------------------------------------------------------------
  // <autogenerated>
  // 本代码由一个工具生成
  // 运行版本：1.0.3705.209
  //
  // 修改本文件将导致异常行为并丢失生成的代码。
  // </autogenerated>
  //------------------------------------------------------------------------------

  unit ASP;

  interface

  uses System.Collections, System.Collections.Specialized, System.Configuration,
   System.Text, System.Text.RegularExpressions, System.Web, System.Web.Caching,
   System.Web.SessionState, System.Web.Security, System.Web.UI, System.Web.UI.WebControls,
   System.Web.UI.HtmlControls, System.Globalization;

  var
   editdemo_aspx___autoHandlers: Integer;
   editdemo_aspx___intialized: Boolean = False;
   editdemo_aspx___fileDependencies: System.Collections.ArrayList;
  type
   editdemo_aspx = class(System.Web.UI.Page, System.Web.SessionState.IRequiresSessionState)
   protected
   Edit1: System.Web.UI.WebControls.TextBox;
   __control3: System.Web.UI.WebControls.Button;
   __control2: System.Web.UI.HtmlControls.HtmlForm;
   Message: System.Web.UI.WebControls.Label;
   procedure ButtonClick(Sender: System.Object; E: EventArgs);
   public
   constructor Create;
   function get_AutoHandlers: Integer; override;
   function get_ApplicationInstance: System.Web.HttpApplication; virtual;
   function get_TemplateSourceDirectory: System.String; override;
   procedure set_AutoHandlers(Value: Integer); override;
   protected
   property AutoHandlers: Integer read get_AutoHandlers write set_AutoHandlers;
   property ApplicationInstance: System.Web.HttpApplication read get_ApplicationInstance;
   public
   property TemplateSourceDirectory: System.String read get_TemplateSourceDirectory;
   private
   function __BuildControlEdit1: System.Web.UI.Control;
   function __BuildControl__control3: System.Web.UI.Control;
   function __BuildControl__control2: System.Web.UI.Control;
   function __BuildControlMessage: System.Web.UI.Control;
   procedure __BuildControlTree(__ctrl: System.Web.UI.Control);
   protected
   procedure FrameworkInitialize; override;
   public
   function GetTypeHashCode: Integer; override;
   end;

  implementation


   procedure editdemo_aspx.ButtonClick(Sender: System.Object; E: EventArgs);
   begin
   Message.Text := Edit1.Text;
   end;
   constructor editdemo_aspx.Create;
  var
   dependencies: System.Collections.ArrayList;
  begin
   inherited Create;

   if (ASP.editdemo_aspx___intialized = False) then
   begin
   dependencies := System.Collections.ArrayList.Create;
   dependencies.Add('d:\vslive\editdemo.aspx');
   ASP.editdemo_aspx___fileDependencies := dependencies;
   ASP.editdemo_aspx___intialized := True;
   end;
   Self.Server.ScriptTimeout := 30000000;
  end;

  function editdemo_aspx.get_AutoHandlers: Integer;
  begin
   Result := ASP.editdemo_aspx___autoHandlers;
  end;

  function editdemo_aspx.get_ApplicationInstance: System.Web.HttpApplication;
  begin
   Result := Self.Context.ApplicationInstance as System.Web.HttpApplication;
  end;

  function editdemo_aspx.get_TemplateSourceDirectory: System.String;
  begin
   Result := '/vslive';
  end;

  procedure editdemo_aspx.set_AutoHandlers(Value: Integer);
  begin
   ASP.editdemo_aspx___autoHandlers := Value;
  end;

  function editdemo_aspx.__BuildControlEdit1: System.Web.UI.Control;
  var
   __ctrl: System.Web.UI.WebControls.TextBox;
  begin

   __ctrl := System.Web.UI.WebControls.TextBox.Create;
   Self.Edit1 := __ctrl;
   __ctrl.ID := 'Edit1';
   __ctrl.Width := System.Web.UI.WebControls.Unit.Parse('300px', System.Globalization.CultureInfo.InvariantCulture);
   Result := __ctrl;
  end;

  function editdemo_aspx.__BuildControl__control3: System.Web.UI.Control;
  var
   __ctrl: System.Web.UI.WebControls.Button;
  begin

   __ctrl := System.Web.UI.WebControls.Button.Create;
   Self.__control3 := __ctrl;
   __ctrl.Text := 'Click Me!';
   __ctrl.add_Click(Self.ButtonClick);
   Result := __ctrl;
  end;

  function editdemo_aspx.__BuildControl__control2: System.Web.UI.Control;
  var
   __parser: System.Web.UI.IParserAccessor;
   __ctrl: System.Web.UI.HtmlControls.HtmlForm;
  begin

   __ctrl := System.Web.UI.HtmlControls.HtmlForm.Create;
   Self.__control2 := __ctrl;
   __parser := __ctrl as System.Web.UI.IParserAccessor;
   __parser.AddParsedSubObject(System.Web.UI.LiteralControl.Create(''#13#10' '));
   Self.__BuildControlEdit1;
   __parser.AddParsedSubObject(Self.Edit1);
   __parser.AddParsedSubObject(System.Web.UI.LiteralControl.Create(''#13#10' '));
   Self.__BuildControl__control3;
   __parser.AddParsedSubObject(Self.__control3);
   __parser.AddParsedSubObject(System.Web.UI.LiteralControl.Create(''#13#10' '));
   Result := __ctrl;
  end;

  function editdemo_aspx.__BuildControlMessage: System.Web.UI.Control;
  var
   __ctrl: System.Web.UI.WebControls.Label;
  begin

   __ctrl := System.Web.UI.WebControls.Label.Create;
   Self.Message := __ctrl;
   __ctrl.ID := 'Message';
   Result := __ctrl;
  end;

  procedure editdemo_aspx.__BuildControlTree(__ctrl: System.Web.UI.Control);
  var
   __parser: System.Web.UI.IParserAccessor;
  begin
   __parser := __ctrl as System.Web.UI.IParserAccessor;
   __parser.AddParsedSubObject(System.Web.UI.LiteralControl.Create('<html>'#13#10' '));
   __parser.AddParsedSubObject(System.Web.UI.LiteralControl.Create(''#13#10' <body>'#13#10' '));
   Self.__BuildControl__control2;
   __parser.AddParsedSubObject(Self.__control2);
   __parser.AddParsedSubObject(System.Web.UI.LiteralControl.Create(''#13#10' <p><b>'));
   Self.__BuildControlMessage;
   __parser.AddParsedSubObject(Self.Message);
   __parser.AddParsedSubObject(System.Web.UI.LiteralControl.Create('</b></p>'#13#10' </body>'#13#10'</html>'#13#10));
  end;

  procedure editdemo_aspx.FrameworkInitialize;
  begin
   Self.__BuildControlTree(Self);
   Self.FileDependencies := ASP.editdemo_aspx___fileDependencies;
   Self.EnableViewStateMac := True;
  end;

  function editdemo_aspx.GetTypeHashCode: Integer;
  begin
   Result := -764444463;
  end;

  end.

  注意：这里介绍的是Delphi的.NET编译器功能的预览。正式发布的Delphi 7生成的代码与上面将有显著不同。本文仅是示例说明如何在ASP.NET中使用Delphi及其功能。

   更高技术的网页
  ASP.net的一些控件远比HTML控件要更加智能化。其中之一就是日历(Calendar)控件。

  以下代码是calendar.aspx中的一部分。代码提供二种方法让控件设置日期：
  　浏览日历然后选择日期；
  　按照日期格式输入日期，确认选择。这种方法由.NET的Convert类支持。

  <script language="Delphi" runat="server">
  procedure Calendar1Selected(Sender: System.Object; E: EventArgs);
  begin
   Label1.Text := 'Delphi for .NET says you picked ' + Calendar1.SelectedDate.ToString('D');
  end;

  procedure Button1Click(Sender: System.Object; E:EventArgs);
  begin
   Calendar1.VisibleDate := System.Convert.ToDateTime(Edit1.Text);
   Label1.Text := 'Delphi for .NET says you set ' + Calendar1.VisibleDate.ToString('D');
  end;
  </script>

  <body Verdana">
   <form runat="server">
   <center>
   <h1>Delphi for .NET running in ASP.NET</h1>
   <p>Please pick a date</p>
   <asp:Calendar id="Calendar1" runat="server" ForeColor="#0000FF" BackColor="#FFFFCC"
   OnSelectionChanged="Calendar1Selected">
   <TodayDayStyle Font-Bold="True"/>
   <NextPrevStyle ForeColor="#FFFFCC"/>
   <DayHeaderStyle BackColor="#FFCC66"/>
   <SelectedDayStyle ForeColor="Black" BackColor="#CCCCFF"/>
   <TitleStyle Font-Size="14pt" Font-Bold="True" ForeColor="#FFFFCC" BackColor="#990000"/>
   <OtherMonthDayStyle ForeColor="#CC9966"/>
   </asp:Calendar>
   <p><asp:TextBox id="Edit1" width=200 runat="server"/>
   <asp:Button text="Set date" id="Button1" runat="server" />
   </p>
   <p><asp:Label id="Label1" runat="server"/></p>
   </center>
   </form>
  </body>

  在日历上选择日期触发OnSelectionChanged事件，调用Delphi的Calendar1Selected()过程。
  输入日期，点击"Set data"按钮触发Button1Click事件，调用Delphi的Button1Click()过程。

  数据处理
  现在通过日历的日期选择来选择显示数据库数据。在这个ASP.NET Delphi网页上，增加一个DataGrid和一个TextBox，前者显示数据库数据，后者输入要显示的数据库域。

  <%Import Namespace="System.Data"%>
  <%Import Namespace="System.Data.SqlClient"%>

  <script language="Delphi" runat="server">
  const
   ProdName = 'Delphi for .NET';
   DispFields = 'OrderID, CustomerID, ShipName, ShipCity, ShipCountry';

  procedure DateSelected(Sender: System.Object; E: EventArgs);
  begin
   Label1.Text := ProdName + ' says you picked ' + Calendar1.SelectedDate.ToString('D');
   DataGrid1.DataSource := GetOrders(Calendar1.SelectedDate);
   DataGrid1.DataBind;
  end;

  procedure Button1Click(Sender: System.Object; E:EventArgs);
  begin
   Calendar1.VisibleDate := System.Convert.ToDateTime(Edit1.Text);
   Label1.Text := ProdName + ' says you set ' + Calendar1.VisibleDate.ToString('D');
  end;

  procedure Button2Click(Sender: System.Object; E:EventArgs);
  begin
   DisplayFields.Text := DispFields;
  end;

  function GetOrders(Date : DateTime) : DataSet;
  var
   Adapter : SqlDataAdapter;
  begin
   Adapter := SqlDataAdapter.Create(
   'select ' + DisplayFields.Text + ' from Orders '+
   'where OrderDate = ''' + date.ToString('d')+'''',
   'Server=(local);Database=Northwind;Trusted_Connection=yes');
   Result := DataSet.Create;
   Adapter.Fill(Result);
  end;

  </script>

  <body Verdana">
   <form runat="server">
   <h1><%=ProdName %> with a Calendar, DataGrid, & SqlClient in ASP.NET</h1>
   <table>
   <tr valign="top"><td>
   <p><b>Pick a date</b></p>
   <asp:Calendar id="Calendar1" runat="server" ForeColor="#0000FF" BackColor="#FFFFCC"
   OnSelectionChanged="DateSelected">
   <TodayDayStyle Font-Bold="True"/>
   <NextPrevStyle ForeColor="#FFFFCC"/>
   <DayHeaderStyle BackColor="#FFCC66"/>
   <SelectedDayStyle ForeColor="Black" BackColor="#CCCCFF"/>
   <TitleStyle Font-Size="14pt" Font-Bold="True" ForeColor="#FFFFCC" BackColor="#990000"/>
   <OtherMonthDayStyle ForeColor="#CC9966"/>
   </asp:Calendar>
   <p><asp:TextBox id="Edit1" width=150 runat="server"/>
   <asp:Button text="Set date" id="Button1" runat="server" />
   </p>
   </td><td valign="top">
   <p><b>Display fields:</b> <asp:TextBox id="DisplayFields"
   text="OrderID, CustomerID, ShipName, ShipCity, ShipCountry" width=500 runat="server"/>
   <asp:Button text="Reset fields" id="Button2" runat="server" /></p>
   <asp:DataGrid id="DataGrid1" runat="server" BorderColor="#FFCC66" ForeColor="#0000FF">
   <HeaderStyle ForeColor="#FFFFCC" BackColor="#990000"/>
   </asp:DataGrid>
   </td></tr></table>
   <p><asp:Label id="Label1" runat="server"/></p>
   </form>
  </body>

  每当用户点击日历选择日期时，就触发OnSelectionChanged事件，调用DateSelected()函数。
  在GetOrders函数中，数据库的连接由命名空间定义的SqlClient实现，数据库是MS SQL 2000的示范库Northwind。SqlDataAdapter将查询结果安装到DataGrid中，显示出数据表格，如附图。

  改变域输入框的域名，再点击日历，就得到不同的结果。

  这就是日历驱动的数据库查询系统，由Delphi for .NET与ASP.NET共同完成。

  结语
  本文试图简略说明在ASP.NET中应用Delphi是如何方便。
  请记住，本文示例是Delphi 7的预览示例，正式版本的结果也许不完全如此，当然也许就是如此。