为了实现点击重新登录系统,设计到的数据库表table(id,name,pwd).点击按钮确定实出现From子句语法错误,小弟知识浅薄,还望各位帮帮忙。
程序如下:
procedure TForm3.Button1Click(Sender: TObject);
var
adoq:TADOQuery;
begin
If Edit1.Text<>'' then
begin
adoq:=TADOQuery.Create(nil);
adoq.Connection:=DataModule2.ADOConnection1;
adoq.SQL.Text:='select * from table where name="'+trim(Edit1.Text)+'"';
adoq.Open;
if not adoq.Eof then
begin
if adoq.FieldByName('pwd').AsString=Edit2.Text then self.ModalResult:=mrOK;
end
else
begin
Messagebox(handle,'密码有误,请重新输入','提示',mb_IconWarning+mb_OK);
Edit2.Clear;
Edit2.SetFocus;
Exit;
end
end
else
begin
Messagebox(handle,'请输入帐号','提示',mb_Iconwarning+mb_OK);
Edit1.SetFocus;
Exit;
end在有就是在主窗体点击弹出登录窗口前提示:
cann't focus a disabled or inbisible window 为什么?
代码:
procedure TForm1.Button1Click(Sender: TObject);
var
Form3:TForm3;
begin
Form3:=TForm3.Create(self);
Form3.ShowModal;
FreeAndNil(Form3);
end;
程序如下:
procedure TForm3.Button1Click(Sender: TObject);
var
adoq:TADOQuery;
begin
If Edit1.Text<>'' then
begin
adoq:=TADOQuery.Create(nil);
adoq.Connection:=DataModule2.ADOConnection1;
adoq.SQL.Text:='select * from table where name="'+trim(Edit1.Text)+'"';
adoq.Open;
if not adoq.Eof then
begin
if adoq.FieldByName('pwd').AsString=Edit2.Text then self.ModalResult:=mrOK;
end
else
begin
Messagebox(handle,'密码有误,请重新输入','提示',mb_IconWarning+mb_OK);
Edit2.Clear;
Edit2.SetFocus;
Exit;
end
end
else
begin
Messagebox(handle,'请输入帐号','提示',mb_Iconwarning+mb_OK);
Edit1.SetFocus;
Exit;
end在有就是在主窗体点击弹出登录窗口前提示:
cann't focus a disabled or inbisible window 为什么?
代码:
procedure TForm1.Button1Click(Sender: TObject);
var
Form3:TForm3;
begin
Form3:=TForm3.Create(self);
Form3.ShowModal;
FreeAndNil(Form3);
end;
2,查看Form3的Visible属性是否为Fasle