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標題: [Delphi] 文字檔案開啟及存檔 [打印本頁]

作者: admin 時間: 2012-3-4 15:14 標題: [Delphi] 文字檔案開啟及存檔

視窗中建立兩個按鍵, 按第一個 "扛開按鍵 " 便啟動檔案對話匣, 讓你點選指定 extension 的檔案 (例如 csv), 然後把檔案內容讀入到strCSV.
按第二個 "存檔按鍵 " 便啟動檔案對話匣, 讓你點選指定 extension 的檔案存檔 (例如 txt), 程式中會把開啟檔案的檔案名自動放入存檔檔案名

public
   strCSV : String;
   CSVFile, TEXTFile : TextFile;
   Openfilename :String;

procedure TfrmConverter.butImportClick(Sender: TObject);
var
  openDialog : TOpenDialog; // Open dialog variable
  strTmp : string;
begin
openDialog := TOpenDialog.Create(self);
openDialog.InitialDir := GetCurrentDir;
openDialog.Options := [ofFileMustExist]; // Only allow existing files to be selected
openDialog.Filter :=  'CSV files|*.csv';

// Display the open file dialog
if openDialog.Execute
then
   begin
      Openfilename :=  openDialog.FileName;
      openDialog.Free; // Free up the dialog
   End
else
   begin
      ShowMessage('Open file was cancelled');
      exit;
   end;

Try
   AssignFile(CSVFile, Openfilename);
   strCSV :='';  //every new import needs to clear strCSV
   Reset(CSVFile);
   while not Eof(CSVFile) do
      begin
         ReadLn(CSVFile, strTmp);
         strCSV := strCSV + strTmp;
      end;
   CloseFile(CSVFile);
Except
   ShowMessage('File Operation Fails');
End;

procedure TfrmConverter.butSaveClick(Sender: TObject);
var
  saveDialog : TSaveDialog; // Save dialog variable
  strTmp2 :String;
  OpenfileLength, Openfilepointer: integer;
begin
  // Create the save dialog object - assign to our save dialog variable
  saveDialog := TSaveDialog.Create(self);
  saveDialog.Title := 'Save your Text File';
  saveDialog.InitialDir := GetCurrentDir;
  saveDialog.Filter := 'Text file|*.txt';
  saveDialog.DefaultExt := 'txt';
  // remove the path of the filename
  Repeat
   OpenfileLength := length(Openfilename);
   Openfilepointer :=Pos('\',Openfilename);
   Openfilename := Copy(Openfilename,Openfilepointer+1,OpenfileLength-Openfilepointer);
  Until (Openfilepointer=0);
  // remove the extension of the filename
  strTmp2 := lowercase(Openfilename);
  Openfilepointer :=Pos('.csv',strTmp2);
  Openfilename := Copy(Openfilename,1,Openfilepointer-1);

  saveDialog.FileName := Openfilename;

  // Display the open file dialog
  if saveDialog.Execute
  then
   begin
      strTmp2 :=  saveDialog.FileName;
      saveDialog.Free;    // Free up the dialog
      Try
      AssignFile(TEXTFile,strTmp2);
      Rewrite(TEXTFile );
      Writeln(TEXTFile ,strCSV );
      closeFile(TEXTFile );
      Except
      ShowMessage('File Operation Fails');
      End;
   End
  else ShowMessage('Save file was cancelled');
End;

作者: admin 時間: 2012-7-9 09:21

以上方法不能存Unicode, 要把 Unicode 存入 CSV 或  TXT

把下面的原來四句

      AssignFile(TEXTFile,strTmp2);
      Rewrite(TEXTFile );
      Writeln(TEXTFile ,strCSV);
      closeFile(TEXTFile );

改為

      { Create a new stream writer directly. }
         Writer := TStreamWriter.Create(strTmp2,false, TEncoding.UTF8);
      { Store the title and then the text. }
         //Writer.WriteLine(''); //add 0D 0A after write the data
         Writer.Write(strCSV);
      { Close and Free the writer. }
         Writer.Free();

之前要加入以下一句在 var 內
  Writer: TStreamWriter;

Header 要加入SysUtils
及 Classes

作者: admin 時間: 2012-11-18 13:40

Appending a line of text to an existing file

var
  myFile : TextFile;
  text : string;

begin

// Try to open the Test.txt file for writing to
  AssignFile(myFile, 'Test.txt');
  ReWrite(myFile);

// Write a couple of well known words to this file
  WriteLn(myFile, 'Hello');
  WriteLn(myFile, 'World');

// Close the file
  CloseFile(myFile);

// Reopen to append a final line to the file

Append(myFile);

// Write this final line
  WriteLn(myFile, 'Final line added');

// Close the file
  CloseFile(myFile);

// Reopen the file for reading
  Reset(myFile);

// Display the file contents
  while not Eof(myFile) do
  begin
ReadLn(myFile, text);
ShowMessage(text);
  end;

// Close the file for the last time
  CloseFile(myFile);
end;

Result
Hello
World
Final line added

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