很简单的问题：有关文件文件操作

Question

var
  MyTextFile: TextFile;
begin
  AssignFile(MyTextFile,'MyTextFile.txt');
  Rewrite(MyTextFile);
  try
    writeln(MyTextFile,'A test Line');
  finally
    CloseFile(MyTextFile);
 end;end.

Answer 1

var
   afile:textfile;
begin
   assignfile(afile,'f:\d.txt');
   rewrite(afile);
   append(afile);
   writeln(afile,'dddd');
   closefile(afile);
end;

Answer 2

给一个完整的程序你吧，作用是从数据表中取出数据，写入txt文件中，如果该文件存在则覆盖。这其中包括建立txt文件名。
unit GZmoneyma;interfaceuses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, TFlatSpeedButtonUnit, KsControls, KsPanels, KsSkinPanels,
  KsHooks, KsForms, KsSkinForms, KsSkinEngine, Db, DBTables, ExtCtrls;type
  TForm16 = class(TForm)
    SeSkinEngine1: TSeSkinEngine;
    SeSkinForm1: TSeSkinForm;
    SeSkinPanel1: TSeSkinPanel;
    FlatSpeedButton1: TFlatSpeedButton;
    FlatSpeedButton2: TFlatSpeedButton;
    Label1: TLabel;
    DataSource1: TDataSource;
    Query1: TQuery;
    Timer1: TTimer;
    DataSource2: TDataSource;
    Table1: TTable;
    procedure FlatSpeedButton2Click(Sender: TObject);
    procedure FlatSpeedButton1Click(Sender: TObject);
    procedure Timer1Timer(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  Form16: TForm16;
  xttime:string;implementation{$R *.DFM}procedure TForm16.FlatSpeedButton2Click(Sender: TObject);
begin
  close;
end;procedure TForm16.FlatSpeedButton1Click(Sender: TObject);
var count,daima,yfmoney:string;
    i,num:integer;
    FileHandle: Integer;
    filevar: textfile;
    buf,name:string;
begin
  //连接数据库GZzong，获取职工所在所代码和银行账号以及应发工资金额，获取记录数
      if query1.active then
         query1.active:=false;
         query1.sql.clear;
         query1.sql.add('select count(*) as recordcounts from GZzong');
         query1.active:=true;
         num:=query1.FieldByName('recordcounts').asinteger;//记录个数
         query1.active:=false;
         query1.sql.clear;
         query1.sql.add('select *  from GZzong');
         query1.Active:=true;
         daima:=query1.fieldbyname('ZGszsdm').asstring;
         query1.active:=false;
  if num<>0 then
    begin
  //获取系统时间，只取月日
      //xttime
  //建立sal*******.txt文件 file.create
         name:='sal'+daima+xttime+'.txt';
         FileHandle := FileCreate(name);
         FileClose(FileHandle);
  //往文件里写入0|账号|金额|1|
         assignfile(filevar,name);
         append(filevar);
         if table1.active=false then
            table1.active:=true;
         Table1.First;
         for i:=1 to num do
           begin
             count:=table1.fieldbyname('ZGcount').asstring;
             yfmoney:=table1.fieldbyname('ZGsfhj').asstring;//应发工资金额
             buf:='0|'+count+'|'+yfmoney+'|1|';
             writeln(filevar,buf);
             Table1.Next;
           end;
           table1.active:=false;
          closefile(filevar);
   end;
   close;
end;
procedure TForm16.Timer1Timer(Sender: TObject);
var datetime:Tdatetime;
    year,month,day:word;
    xt3,xt4:integer;
    xt1,xt2:string;
begin
  datetime:=now;
  decodedate(datetime,year,month,day);
  xt1:=inttostr(month);
  xt2:=inttostr(day);
  xt3:=strtoint(xt1);
  xt4:=strtoint(xt2);
  if (xt3<=9)and(xt4<=9) then
     xttime:='0'+xt1+'0'+xt2
     else
      if (xt3<=9)and(xt4>9) then
       xttime:='0'+xt1+xt2
        else
         if (xt3>9)and(xt4<=9) then
           xttime:=xt1+'0'+xt2
           else
            xttime:=xt1+xt2;
end;end.

Answer 3

var
  TestFile: TextFile;
begin
  AssignFile(TestFile,'d:\Test.txt');//在D盘创建一个test.txt文件
  Rewrite(TestFile);
  try
    writeln(TestFile,'文件操作测试！');
  finally
    CloseFile(TestFile);//关闭文件
 end;

Answer 4

procedure TForm1.Button1Click(Sender: TObject);
var
  txtFile : TextFile;
  FileName: String;
begin
  FileName := 'C:\1.txt';
  if FileExists(FileName) then
    DeleteFile(FileName)
  else FileCreate(FileName);
    AssignFile(txtFile,FileName);
  ReWrite(txtFile);
  write(txtFile,'cccccc');
  CloseFile(txtFile);
end;

Answer 5

去看一下《Delphi5开发人员指南》这本书吧，你的基础还不牢，这样一个个地问问题不是办法的。