入门问题:请问“This form of method call only allowed of class methods”错误的原因何在？

是不是在自已的窗体中调用方法用了form1.()?

程序是这样的:
unit Unit14;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ToolWin, ComCtrls, ExtCtrls, DB, Grids, DBGrids, DBReportGrid,
  ADODB, StdCtrls;type
  TForm14 = class(TForm)
    Panel1: TPanel;
    StatusBar1: TStatusBar;
    ADODataSet1: TADODataSet;
    DataSource1: TDataSource;
    Panel2: TPanel;
    Label2: TLabel;
    Label1: TLabel;
    DateTimePicker1: TDateTimePicker;
    DateTimePicker2: TDateTimePicker;
    Label3: TLabel;
    Button1: TButton;
    DBGrid1: TDBGrid;
    Label4: TLabel;
    Label5: TLabel;
    ADODataSet1DSDesigner: TStringField;
    ADODataSet1DSDesigner2: TBCDField;
    ADODataSet1DSDesigner3: TIntegerField;
    Panel4: TPanel;
    ADODataSet1DSDesigner4: TIntegerField;
    procedure FormCreate(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure FormDestroy(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  Form14: TForm14;
  procedure KSSR;implementationuses ConnectDM, DBRoutines,ExportTo;
procedure KSSR;
begin
if Form14=nil then
    Form14:=TForm14.Create(Application)
  else
    Form14.Show;end;
{$R *.dfm}procedure TForm14.FormCreate(Sender: TObject);
var
aa: string[28] ;
bb: string[28] ;
cc: string[28] ;
Y, M, D: WORD;begin
  aa:=DateToStr(Date);
  bb:=copy(aa,1,5);
  bb:=bb+'.20';
  DecodeDate(Date(), Y, M, D);
  if M>1 then
    M:=M-1
  else begin
    Y:=Y-1;
    M:=12;
  end;
  cc:=IntToStr(Y)+'.';
  if M<10 then
    cc:=cc+'0'+IntToStr(M)
  else
    cc:=cc+IntToStr(M);
    cc:=cc+'.21';
  DateTimePicker1.DateTime:=StrToDate(cc);
  DateTimePicker2.DateTime:=StrToDate(bb);
  Panel4.Caption:='说明：因数据量大，故计算时间较长';
  //DateTimePicker1.DateTime:=Date ;
  //DateTimePicker2.DateTime:=Date ;
  end;
procedure TForm14.FormClose(Sender: TObject; var Action: TCloseAction);
begin
ADODataSet1.Close;
DataObject.qryHelper.Close;
DataObject.qryHelper1.Close;
Action:=caFree;
end;procedure TForm14.FormDestroy(Sender: TObject);
begin
Form14:=nil;
end;procedure TForm14.Button1Click(Sender: TObject);
var
Sum1:Double;
Sum2:Double;
Sum3:Double;
begin  with ADODataSet1 do
  begin
        Close;
//        ShowMessage(DateToStr(DateTimePicker1.Date));
        CommandText:='Execute an_Manager1 :startdate, :enddate';
        Parameters[0].Value:=DateTimePicker1.Date;
        Parameters[1].Value:=DateTimePicker2.Date+1;
        Open;
  end;
  with DataObject.qryHelper do
  begin
    Close;
    SQL.Text:='select convert(decimal(12,2),sum(实付单价*数量)) from 门诊费用_head a join 门诊费用_data b on a.序号=b.序号 where 日期 between :startdate and :enddate ';
    Parameters[0].Value:=DateTimePicker1.Date;
    Parameters[1].Value:=DateTimePicker2.Date+1;
    Open;
    Sum1:=Fields[0].AsFloat;
    Close;
  end;
  with DataObject.qryHelper1 do
  begin
    Close;
    SQL.Text:='select convert(decimal(12,2),sum(单价*数量)) from 住院费用 where 日期 between :startdate and :enddate ';
    Parameters[0].Value:=DateTimePicker1.Date;
    Parameters[1].Value:=DateTimePicker2.Date+1;
    Open;
    Sum2:=Fields[0].AsFloat;
    Close;
  end;
  TDBGridExport.Export_To_Excel(DBGrid1);
  sum3:=Sum1+Sum2;
  Panel4.Caption:='门诊收入：'+FloatToStr(Sum1)+'       住院收入：'+FloatToStr(Sum2)+'       总收入：'+FloatToStr(Sum3);end;end.
TDBGridExport.Export_To_Excel(DBGrid1);这句提示错误,请指点一下,谢谢

unit   ExportTo;
interface
uses
    SysUtils,   Classes,   Graphics,   Controls,   Forms,   Dialogs,StdCtrls,   Db,   DBGrids,   Comobj,   extctrls,   comctrls,   ActiveX;
type
    TSpaceMark   =   (csComma,   csSemicolon,   csTab,   csBlank,   csEnter);
    TDBGridExport   =   class(TComponent)
    private
        FDB_Grid:   TDBGrid;   {读取DBGrid的源}
        FTxtFileName:   string;   {文本文件名}
        FSpaceMark:   TSpaceMark;   {间隔符号}
        FSpace_Ord:   Integer;   {间隔符号的Asc数值}
        FTitle:   string;   {显示的标题}
        FSheetName:   string;   {工作表标题}
        FExcel_Handle:   OleVariant;   {Excel的句柄}
        FWorkbook_Handle:   OleVariant;   {书签的句柄}
        FShow_Progress:   Boolean;   {是否显示插入进度}
        FProgress_Form:   TForm;   {进度窗体}
        FRun_Excel_Form:   TForm;   {启动Excel提示窗口}
        FProgressBar:   TProgressBar;   {进度条}
        function   Connect_Excel:   Boolean;   {启动Excel}
        function   New_Workbook:   Boolean;   {插入新的工作博}
        function   InsertData_To_Excel:   Boolean;   {插入数据}
        procedure   Create_ProgressForm(AOwner:   TComponent);   {创建进度显示窗口}
        procedure   Create_Run_Excel_Form(AOwner:   TComponent);   {创建启动Excel窗口}
        //procedure   SetSpaceMark(Value:   TSpaceMark);   {设置导出时的间隔符号}
        protected
    public
        constructor   Create(AOwner:   TComponent);   override;   {新建}
        destructor   Destroy;   override;   {销毁}
        function   Export_To_Excel:   Boolean;   overload;   {导出到Excel中}
        function   Export_To_Excel(DB_Grid:   TDBGrid):   Boolean;   overload;
        function   Export_To_Txt(NewFile:   Boolean   =   True):   Boolean;   overload;   {导出到文本文件中}
        function   Export_To_Txt(FileName:   string;   NewFile:   Boolean   =   True):   Boolean;   overload;
        function   Export_To_Txt(DB_Grid:   TDBGrid;   NewFile:   Boolean   =   True):   Boolean;   overload;
        function   Export_To_Txt(FileName:   string;   DB_Grid:   TDBGrid;   NewFile:   Boolean   =   True):   Boolean;   overload;
        published
        property   DB_Grid:   TDBGrid   read   FDB_Grid   write   FDB_Grid;
        property   Show_Progress:   Boolean   read   FShow_Progress   write   FShow_Progress;
        property   TxtFileName:   string   read   FTxtFileName   write   FTxtFileName;
  //      property   SpaceMark:   TSpaceMark   read   FSpaceMark   write   SetSpaceMark;
        property   Title:   string   read   FTitle   write   FTitle;
        property   SheetName:   string   read   FSheetName   write   FSheetName;
end; procedure   Register;implementation procedure   Register;begin
    RegisterComponents( 'Stone',   [TDBGridExport]);
end;
{-------------------------------------------------------------------------------}
{新建}
constructor   TDBGridExport.Create(AOwner:   TComponent);
begin
    inherited   Create(AOwner);
    FShow_Progress   :=   True;
    FSpaceMark   :=   csTab;
end;{销毁}
destructor   TDBGridExport.Destroy;
begin
    varClear(FExcel_Handle);
    varClear(FWorkbook_Handle);
inherited   Destroy;
end;
{===============================================================================}
{导出到文本文件中}
function   TDBGridExport.Export_To_Txt(NewFile:   Boolean   =   True):   Boolean;
var
    Txt:   TStrings;
    Tmp_Str,data_Str,Column_name:   string;
    i,   j:   Integer;
    Data_Set:   TDataSet;
    book:   pointer;
    Before_Scroll,   Afrer_Scroll:   TDataSetNotifyEvent;
begin
    Result   :=   False;
    if   NewFile   =   True   then
        FTxtFileName   :=   ' ';
    if   FTxtFileName   =   ' '   then
    begin
        with   TSaveDialog.Create(nil)   do
        begin
            Title   :=   '请选择输出文件名 ';
            DefaultExt   :=   'txt ';
            Filter   :=   '文本文件(*.Txt) |*.txt ';
            Options   :=   [ofOverwritePrompt,   ofHideReadOnly,   ofPathMustExist,   ofNoReadOnlyReturn,   ofEnableSizing];
            if   Execute   then
                FTxtFileName   :=   FileName;
            Free;
            if   FTxtFileName   =   ' '   then   {如果没有选中文件，则直接推出}
            exit;
        end;         if   FTxtFileName   =   ' '   then
        begin
            raise   exception.Create( '没有指定输出文件 ');
            Exit;
        end;
    end;
    if   FDB_Grid   =   nil   then
        raise   exception.Create( '请输入DBGrid名称 ');
    Txt   :=   TStringList.Create;
    try{显示插入进度}
        if   FShow_Progress   =   True   then
        begin
            Create_ProgressForm(nil);
            FProgress_Form.Show;
        end;
        {第一行，插入标题}
        Tmp_Str   :=   ' ';   //FDB_Grid.Columns[0].Title.Caption;
        for   i   :=   1   to   FDB_Grid.Columns.Count   do
        if   FDB_Grid.Columns[i   -   1].Visible   =   True   then
            Tmp_Str   :=   Tmp_Str   +   FDB_Grid.Columns[i   -   1].Title.Caption   +   Chr(FSpace_Ord);
        Tmp_Str   :=   Copy(Tmp_Str,   1,   Length(Tmp_Str)   -   1);
        Txt.Add(Tmp_Str);
        {插入DBGrid中的数据}
        Data_Set   :=   FDB_Grid.DataSource.DataSet;
        {记忆当前位置并取消任何事件}
        //   new(book);
        book   :=   Data_Set.GetBook;
        Data_Set.DisableControls;
        Before_Scroll   :=   Data_Set.BeforeScroll;
        Afrer_Scroll   :=   Data_Set.AfterScroll;
        Data_Set.BeforeScroll   :=   nil;
        Data_Set.AfterScroll   :=   nil;
        if   FShow_Progress   =   True   then
        begin
            Data_Set.Last;
            FProgress_Form.Refresh;
            FProgressBar.Max   :=   Data_Set.RecordCount;
        end;
        {插入DBGrid中的所有字段}
        Data_Set.First;
        j   :=   2;
        while   not   Data_Set.Eof   do
        begin
            if   FShow_Progress   =   True   then
                FProgressBar.Position   :=   j   -   2;
            Column_name   :=   FDB_Grid.Columns[0].FieldName;
            Tmp_Str   :=   ' ';   //Data_Set.FieldByName(Column_name).AsString;
            for   i   :=   1   to   FDB_Grid.Columns.Count   do
                if   FDB_Grid.Columns[i   -   1].Visible   =   True   then
                begin
                    data_Str   :=   FDB_Grid.Fields[i   -   1].DisplayText;
                    Tmp_Str   :=   Tmp_Str   +   data_Str   +   Chr(FSpace_Ord);
                end;
            Tmp_Str   :=   Copy(Tmp_Str,   1,   Length(Tmp_Str)   -   1);
            Txt.Add(Tmp_Str);
            j   :=   j   +   1;
            Data_Set.Next;
        end;
        {恢复原始事件以及标志位置}
        Data_Set.GotoBook(book);
        Data_Set.FreeBook(book);
        //   dispose(book);
        Data_Set.EnableControls;
        Data_Set.BeforeScroll   :=   Before_Scroll;
        Data_Set.AfterScroll   :=   Afrer_Scroll;
        {写到文件}
        Txt.SaveToFile(FTxtFileName);
        Result   :=   True;
    finally
        Txt.Free;
        if   FShow_Progress   =   True   then
        begin
            FProgress_Form.Free;
            FProgress_Form   :=   nil;
        end;
    end;
end;
function   TDBGridExport.Export_To_Txt(FileName:   string;   NewFile:   Boolean   =   True):   Boolean;
begin
    FTxtFileName   :=   FileName;
    Result   :=   Export_To_Txt(NewFile);
end; function   TDBGridExport.Export_To_Txt(DB_Grid:   TDBGrid;   NewFile:   Boolean   =   True):   Boolean;
begin
    FDB_Grid   :=   DB_Grid;
    Result   :=   Export_To_Txt(NewFile);
end; function   TDBGridExport.Export_To_Txt(FileName:   string;   DB_Grid:   TDBGrid;   NewFile:   Boolean   =   True):   Boolean;
begin
    FTxtFileName   :=   FileName;
    FDB_Grid   :=   DB_Grid;
    Result   :=   Export_To_Txt(NewFile);
end;

貌似2楼翻译错了，我来给个正确的翻译：“只有类方法才允许这种方法调用的方式”。很明显，TDBGridExport.Export_To_Excel(DBGrid1)，你是企图想用类方法的调用方式来调用这个函数，但是“Export_To_Excel”并不是一个类方法。因此你必须先创建TDBGridExport的实例，然后才能调用到这个方法。

如果先创建这个类就可以直接调用。不创建类，可以class function TDBGridExport.Export_To_Txt(NewFile: Boolean = True): Boolean; 这样写

调试易

入门问题:请问“This form of method call only allowed of class methods”错误的原因何在？

解决方案 »