氢氧化亚铁灰绿色:Asp.net 登陆代码问题

sub addclick (sender as object,e as eventargs)
if textbox1.text="" then
s.text="请输入用户名"
else
dim mysql as new sqlconnection
mysql=new sqlconnection("server=local;database=business;uid=sa;pwd=sa")
dim sqlcmd as new sqlcommand
dim mystr as string
dim mystr1 as string
dim mystr2 as string="select id,pwd from Tab_customer where id='&trim(textbox1.text)&'"
mysql.open()
sqlcmd =new sqlcommand(mystr2,mysql)
dim user as sqldatareader=sqlcmd.executereader()
while user.read()
mystr=user.item(0)
mystr1=user.item(1)
end while
mysql.close()
if mystr="" then
s.text="用户名不存在,请重新输入"
textbox1.text=""
textbox2.text=""

else
if textbox2.text=mystr1 then
s.text="成功登陆!"
else s.text="密码错误,请重新输入"
textbox1.text=""
textbox2.text=""
end if
end if
end if
end sub
sub cancelclick (sender as object,e as eventArgs)
s.text=""
textbox1.text=""
textbox2.text=""
end sub

以上是脚本部分的代码(vb),但是当我运行的时候,就算我输入的用户和密码是对的,它仍然说我的用户名不存在,怎么回事?难道dim mystr2 as string="select id,pwd from Tab_customer where id='&trim(textbox1.text)&'"
这句代码不行?但是调试的时候没说错误啊
是不是 mystr=user.item(0)
mystr1=user.item(1)
这两个代码有问题?
我的表的设计是:
create table Tab_customer
(
Id varchar(10) not null,
pwd varchar(10),
Khname varchar(100),
Khjc varchar(50),
Address varchar(100),
Postcode varchar(50),
Tel varchar(50),
Fax varchar(50),
Lxr varchar(50),
Lxrtel varchar(50),
yhzh varchar(50),
Khyh varchar(50),
primary key(Id)
)
已经好了
你们说的只对了一半，是那个select语句有问题,但是你们给出的句子也不对,应该是dim mystr2 as string="select id,pwd from Tab_customer where id='"&trim(textbox1.text)&"'"
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