继承统计查询窗体后 点查询时报错**

jiahaiming

主要还是对类库的熟悉。
在平台里有专门的对话框组件可以使用（在论坛、手册里都有介绍）：
NameSpace: Business.Forms
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Dialogs = class(System.Object)
public
  MaxCustomColors: Shortint;
  mbAbortIgnore: .$$TD-D3CF0D7AC97348BF97319A50103BE4FB;
  mbAbortRetryIgnore: .$$TD-AE814720C69E46018F8C6B793A586A8D;
  mbOKCancel: .$$TD-481A5F02C3694EF4BBE2F31FD54781CD;
  mbYesAllNoAllCancel: .$$TD-BA246D01BFD348EE9AEEA6E702012C85;
  mbYesNoCancel: .$$TD-1CB2A61828344507988BC3BDBC16C979;
  static function CreateMessageDialog(Msg: string; DlgType: TMsgDlgType; Buttons: TMsgDlgButtons): TFormControl;
  static function InputBox(ACaption: string; APrompt: string; ADefault: string): string;
  static function InputQuery(ACaption: string; APrompt: string; Value: string): Boolean;
  static function MessageDlg(Msg: string; DlgType: TMsgDlgType; Buttons: TMsgDlgButtons; HelpCtx: Longint): Longint;
  static function MessageDlgPos(Msg: string; DlgType: TMsgDlgType; Buttons: TMsgDlgButtons; HelpCtx: Longint; X: Longint; Y: Longint): Longint;
  static function MessageDlgPosHelp(Msg: string; DlgType: TMsgDlgType; Buttons: TMsgDlgButtons; HelpCtx: Longint; X: Longint; Y: Longint; HelpFileName: string): Longint;
  static function PromptForFileName(AFileName: string; AFilter: string; ADefaultExt: string; ATitle: string; AInitialDir: string; SaveDialog: Boolean): Boolean;
  static procedure ShowMessage(Msg: string);
  static procedure ShowMessageFmt(Msg: string; Params: array of TObject);
  static procedure ShowMessagePos(Msg: string; X: Longint; Y: Longint);
  property ForceCurrentDirectory: Boolean;
end;

zfang

请楼主反馈下。