即使条件为假，也会将信息上传到数据库

Question

我有一个表单，它通过编辑框和组合框从用户那里获取数据，然后必须将这些信息上传到数据库表中，所以我必须进行验证。我就是这么做的，它一直在说"不是一个有效的整数"，但它甚至不应该上传任何东西到数据库表，因为我做了空检查，所有条件都不满足。我的验证做错了吗？

unit Unit6;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, Spin, ExtCtrls,unit7,unit5,unit4, DB, ADODB, Grids, DBGrids,
pngimage;
type
Tfrmupload = class(TForm)
Panel1: TPanel;
edtname: TEdit;
edtsurn: TEdit;
edtidn: TEdit;
Label1: TLabel;
Label2: TLabel;
Label3: TLabel;
Label5: TLabel;
Label6: TLabel;
Panel2: TPanel;
btnupload: TButton;
edtmail: TEdit;
cbprov: TComboBox;
Image1: TImage;
cbdiv: TComboBox;
Label4: TLabel;
procedure btnuploadClick(Sender: TObject);
procedure Label7Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
frmupload: Tfrmupload;

implementation
{$R *.dfm}
procedure Tfrmupload.btnuploadClick(Sender: TObject);
var
vname,vsurname,today,c,vidn,vprov,vmail,vdiv:string;
vage,year,i,age:integer;
bnotnull,bIDL,bmail,bage,byoung,valid,idrepeated:boolean;
dt:tdatetime;
begin
vname:=edtname.Text;
vsurname:=edtsurn.Text;
vidn:=edtidn.Text;
vdiv:=cbdiv.Text;
vprov:=cbprov.Text;
vmail:=edtmail.Text;
//booleans
bnotnull:=false;
bIdL:=false;
bmail:=false;
byoung:=false;
idrepeated:=false;
valid:=false;
//check if id entered is not in table already
if unit5.frmadmin.ADODetails.Locate('ID number',vidn,[]) then
begin
idrepeated:=true;
showmessage('ID Number already exists');
end;


//null check
if (vname<>'')and(vsurname<>'')and(vidn<>'')and(vprov<>'')and(vmail<>'')and(vdiv<>'') then
begin
bnotnull:=true;
end
else
begin
Showmessage('Complete All Fields!');
end;
//get current date
dt:=now;
year:=strtoint(formatdatetime('yyyy',dt));
c:=copy(vidn,1,2);
//calculate age from id number
if (strtoint(c)>=0) and (strtoint(c)<=22) then
begin
age:=year-(2000+strtoint(c));
end
else
begin
age:=year-(1900+strtoint(c));
end;
//ID length validation
if (length(vidn)=13) then
begin
bidl:=true;
end;

//check if contestant is not too young
if age<6 then
begin
showmessage('Contestant too young, cannot compete');
byoung:=true;
end;
//check if email is correct format
for i := 1 to length(vmail)do
begin
if vmail[i]='@' then
begin
bmail:=true;
end;
end;
//error message for email check
if bmail=false then
begin
showmessage('Incorrect Email Format');
end;
if bidl=false then
begin
showmessage('ID Number must be 13 characters');
end;
//checks if all the conditions are met and if so we can then upload to database
if (bnotnull=true) and (bidl=true) and (byoung=false)and (bmail=true)and (idrepeated=false) then
begin
valid:=true;
end;
if valid=true then
begin
unit5.frmadmin.ADODetails.Append;
unit5.frmadmin.ADODetails['Name(s)']:=vname;
unit5.frmadmin.ADODetails['Surname']:=vsurname;
unit5.frmadmin.ADODetails['ID Number']:=vidn;
unit5.frmadmin.ADODetails['Age']:=age;
unit5.frmadmin.ADODetails['Province']:=vprov;
unit5.frmadmin.ADODetails['Email']:=vmail;
unit5.frmadmin.ADODetails.Post;

unit4.frmcontest.ADOLead.Insert;
unit4.frmcontest.ADOLead['ID Number']:=unit4.frmcontest.DBComboID.Text;;
unit4.frmcontest.ADOLead['Name(s)']:=unit4.frmcontest.DBCombonme.Text;
unit4.frmcontest.ADOLead['Division']:=vdiv;
unit4.frmcontest.ADOLead.Post;
showmessage('Details Uploaded');
frmupload.Hide;
end;

//clears all inputs
edtname.Clear;
edtsurn.Clear;
edtidn.Clear;
cbdiv.Text:='';
cbprov.Text:='';
edtmail.Clear;

end;
procedure Tfrmupload.Label7Click(Sender: TObject);
begin
frmupload.Hide;
end;
end.

Answer 1

我认为我们需要看到一个示例数据库记录，该记录是在错误条件下保存到数据库的。此外，您可以通过将Trim((函数应用于编辑框的输入来采取预防措施

vname:=Trim(edtname.Text);
vsurname:=Trim(edtsurn.Text);
vidn:=Trim(edtidn.Text);
vdiv:=Trim(cbdiv.Text);
vprov:=Trim(cbprov.Text);
vmail:=Trim(edtmail.Text);

您还可以检查变量vidn的长度

If Length(vidn) < 4 then
//or
If Length(vidn) < 2 then

Answer 2

这个错误非常明显。您有strtoint(又名STRING to INT(，但您给它一个格式化的日期时间。

year:=strtoint(formatdatetime('yyyy',dt));

我不明白为什么你可以用2022的值作为整数来表示年份，但如果你坚持这样做，你可以先格式化dt，然后使用datetimetostr，再使用strtoint。另一件可以减少代码和工作并使一切变得更容易的事情是DB感知组件。它们所做的是，一旦你将它们连接到数据库以及你正在处理的表和列，它们就会自动进行更新或插入。您所需要做的就是TMSQuery.插入，然后TMSQuery.添加新行时发布，以及TMSQuery.编辑和TMSQuery.更改值时发布。