Экспорт ADO таблиц в разные форматы

Автор: http://www.swissdelphicenter.ch

{
Exporting ADO tables into various formats

In this article I want to present a component I built in order to
supply exporting features to the ADOTable component. ADO supplies
an extended SQL syntax that allows exporting of data into various
formats. I took into consideration the following formats:

1)Excel
2)Html
3)Paradox
4)Dbase
5)Text

You can see all supported output formats in the registry:
"HKEY_LOCAL_MACHINE\Software\Microsoft\Jet\4.0\ISAM formats"

 This is the complete source of my component }

unit ExportADOTable;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Db, ADODB;

type
  TExportADOTable = class(TADOTable)
  private
    { Private declarations }
    //TADOCommand component used to execute the SQL exporting commands
    FADOCommand: TADOCommand;
  protected
    { Protected declarations }
  public
    { Public declarations }
    constructor Create(AOwner: TComponent); override;

    //Export procedures
    //"FiledNames" is a comma separated list of the names of the fields you want to export
    //"FileName" is the name of the output file (including the complete path)
    //if the dataset is filtered (Filtered = true and Filter <> ""), then I append
    //the filter string to the sql command in the "where" directive
    //if the dataset is sorted (Sort <> "") then I append the sort string to the sql command in the
    //"order by" directive

    procedure ExportToExcel(FieldNames: string; FileName: string;
      SheetName: string; IsamFormat: string);
    procedure ExportToHtml(FieldNames: string; FileName: string);
    procedure ExportToParadox(FieldNames: string; FileName: string; IsamFormat:
      string);
    procedure ExportToDbase(FieldNames: string; FileName: string; IsamFormat:
      string);
    procedure ExportToTxt(FieldNames: string; FileName: string);
  published
    { Published declarations }
  end;

procedure Register;

implementation

procedure Register;
begin
  RegisterComponents("Carlo Pasolini", [TExportADOTable]);
end;

constructor TExportADOTable.Create(AOwner: TComponent);
begin
  inherited;

  FADOCommand := TADOCommand.Create(Self);
end;

procedure TExportADOTable.ExportToExcel(FieldNames: string; FileName: string;
  SheetName: string; IsamFormat: string);
begin
  {IsamFormat values
   Excel 3.0
   Excel 4.0
   Excel 5.0
   Excel 8.0
  }

  if not Active then
    Exit;
  FADOCommand.Connection := Connection;
  FADOCommand.CommandText := "Select " + FieldNames + " INTO " + "[" +
    SheetName + "]" + " IN " + """ + FileName + """ + "[" + IsamFormat +
    ";]" + " From " + TableName;
  if Filtered and (Filter <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " where " + Filter;
  if (Sort <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " order by " + Sort;
  FADOCommand.Execute;
end;

procedure TExportADOTable.ExportToHtml(FieldNames: string; FileName: string);
var
  IsamFormat: string;
begin
  if not Active then
    Exit;

  IsamFormat := "HTML Export";

  FADOCommand.Connection := Connection;
  FADOCommand.CommandText := "Select " + FieldNames + " INTO " + "[" +
    ExtractFileName(FileName) + "]" +
    " IN " + """ + ExtractFilePath(FileName) + """ + "[" + IsamFormat +
    ";]" + " From " + TableName;
  if Filtered and (Filter <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " where " + Filter;
  if (Sort <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " order by " + Sort;
  FADOCommand.Execute;
end;

procedure TExportADOTable.ExportToParadox(FieldNames: string;
  FileName: string; IsamFormat: string);
begin
  {IsamFormat values
  Paradox 3.X
  Paradox 4.X
  Paradox 5.X
  Paradox 7.X
  }
  if not Active then
    Exit;

  FADOCommand.Connection := Connection;
  FADOCommand.CommandText := "Select " + FieldNames + " INTO " + "[" +
    ExtractFileName(FileName) + "]" +
    " IN " + """ + ExtractFilePath(FileName) + """ + "[" + IsamFormat +
    ";]" + " From " + TableName;
  if Filtered and (Filter <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " where " + Filter;
  if (Sort <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " order by " + Sort;
  FADOCommand.Execute;
end;

procedure TExportADOTable.ExportToDbase(FieldNames: string; FileName: string;
  IsamFormat: string);
begin
  {IsamFormat values
  dBase III
  dBase IV
  dBase 5.0
  }
  if not Active then
    Exit;

  FADOCommand.Connection := Connection;
  FADOCommand.CommandText := "Select " + FieldNames + " INTO " + "[" +
    ExtractFileName(FileName) + "]" +
    " IN " + """ + ExtractFilePath(FileName) + """ + "[" + IsamFormat +
    ";]" + " From " + TableName;
  if Filtered and (Filter <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " where " + Filter;
  if (Sort <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " order by " + Sort;
  FADOCommand.Execute;
end;

procedure TExportADOTable.ExportToTxt(FieldNames: string; FileName: string);
var
  IsamFormat: string;
begin
  if not Active then
    Exit;

  IsamFormat := "Text";

  FADOCommand.Connection := Connection;
  FADOCommand.CommandText := "Select " + FieldNames + " INTO " + "[" +
    ExtractFileName(FileName) + "]" +
    " IN " + """ + ExtractFilePath(FileName) + """ + "[" + IsamFormat +
    ";]" + " From " + TableName;
  if Filtered and (Filter <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " where " + Filter;
  if (Sort <> "") then
    FADOCommand.CommandText := FADOCommand.CommandText + " order by " + Sort;
  FADOCommand.Execute;
end;

end.

{
Note that you can use an already existing database as destination but not an already existing
table in the database itself: if you specify an already exixting table you will receive
an error message. You might insert a verification code inside every exporting procedure of my
component, before the execution of the sql exporting command, in order to send a request of
deleting the already present table or aborting the exporting process.

carlo Pasolini, Riccione(italy), e-mail: ccpasolini@libero.it
}

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