C++builder下的数据库问题~~~~

wahaha2000

我用C++builder编写一个用户注册和修改密码的程序，使用ADO控件访问本机ACCESS数据库
我编写的程序如下：
//---------------------------------------------------------------------------

#include <vcl.h>;
#pragma hdrstop

#include "login1.h"
#include "RIGHT2.h"
#include "Unit3.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
       : TForm(Owner)
{
}
//---------------------------------------------------------------------------




void __fastcall TForm1::Button1Click(TObject *Sender)
{
ADOQuery1->;Open();
ADOQuery1->;Close();
ADOQuery1->;SQL->;Clear();
ADOQuery1->;SQL->;Add("Select USERCODE,USERNAME,PASSWORD from USER_INFO where USERCODE='"+Edit1->;Text+"'";
if(Edit1->;Text==""
{ShowMessage("请输入帐户名！";
return;
}
if(NewAcctNameEdit->;Text==""
{ShowMessage("请输入用户名！";
return;
}
ADOQuery1->;Open();
if (!(ADOQuery1->;IsEmpty()))
{ShowMessage("此帐户已存在！";
return;
}


ADOQuery1->;Append();

if(NewAcctCommentEdit->;Text!=NewAcctPwdConfirmMaskEdit->;Text)
{ShowMessage("两次输入密码不相同";
return;
}
ADOQuery1->;FieldByName("USERCODE"->;AsString=Edit1->;Text;
ADOQuery1->;FieldByName("USERNAME"->;AsString=NewAcctNameEdit->;Text;
ADOQuery1->;FieldByName("ASSWORD"->;AsString=NewAcctCommentEdit->;Text;
ADOQuery1->ost();
ADOQuery1->;Close();
ADOQuery1->;Open();
Form2->;Show();
Form1->;Hide();

}
//---------------------------------------------------------------------------


void __fastcall TForm1::Button2Click(TObject *Sender)
{
Edit1->;Text="";
NewAcctNameEdit->;Text="";
NewAcctCommentEdit->;Text="";
NewAcctPwdConfirmMaskEdit->;Text="";
}
//---------------------------------------------------------------------------



void __fastcall TForm1::Button3Click(TObject *Sender)
{
ADOQuery1->;Close();
ADOQuery1->;SQL->;Clear();
ADOQuery1->;SQL->;Add("Select USERCODE,PASSWORD from USER_INFO where USERCODE='"+EditAcctNameEdit->;Text+"'");
ADOQuery1->;Open();
if(EditAcctNameEdit->;Text=="")
{ShowMessage("请输入帐户名！");
return;
}
if(ADOQuery1->;IsEmpty())
{ShowMessage("此帐户不存在！");
return;
}

if(EditAcctOldPwdMaskEdit->;Text=="")
{ShowMessage("请输入旧密码！");
return;
}
if(EditAcctOldPwdMaskEdit->;Text!=ADOQuery1->;FieldByName("ASSWORD")->;AsString);
{ShowMessage("旧密码错误！");
return;
}
ShowMessage("旧密码正确");
if(EditAcctNewPwdMaskEdit->;Text!=EditAcctPwdConfirmMaskEdit->;Text)
{ShowMessage("两次输入的密码不相同！");
return;
}
ADOQuery1->;Append();
ADOQuery1->;FieldByName("ASSWORD")->;AsString=EditAcctNewPwdMaskEdit->;Text;
ADOQuery1->ost();
ADOQuery1->;Close();
ShowMessage("新密码已生效！");
return;
}

//---------------------------------------------------------------------------
程序编译通过
用户注册部分程序没有问题
但是修改密码部分不管我输入的旧密码是对的还是错的，程序都会弹出“旧密码错误”的提示筐，请问是什么原因，应该怎么改正？

wahaha2000

有人知道错在那里吗？我实在是搞不懂了。请高手指正