How to find the invalid username?

[JCel]

Hi here how to inform that the user has entered wrong username/invalid

username...

The scenerio is:

userId=txtUser.text
userPwd=txtPwd.text

If myReader.HasRows Then
Do While myReader.Read
If userId = myReader(0) then
if userPwd = myReader(1) Then
Messagebox.show("Welcome")'here it enters if both username & password

is valid
else
Messagebox.show("Wrong password")'here username is correct,but pwd is

not valid

End If
End if
Loop
End if

'Now what in case of invalid username?

 

[Robert_Zenz]

What do you mean what to do in case of a wrong username/password? Do nothing, inform the user that he entered the wrong details and leave him with the login-form alone.

Bobby

 

[JCel]

Hi all,

The actual scenerio is:

userId=txtUser.text
userPwd=txtPwd.text

If myReader.HasRows Then
Do While myReader.Read
If userId = myReader(0) then
if userPwd = myReader(1) Then
Messagebox.show("Welcome")'here it enters if both username & password

is valid
else
Messagebox.show("Wrong password")'here username is correct,but pwd is

not valid

End If
'Now i want to tell the user that he has entered wrong username... I tried else here but it displays the messagebox dialog as many times the records found in the DB... Eg. if i have 6 records messagebox is displaying for 6 times... its bcoz the else is inside the loop.. so plz tell me how to do it?
End if
Loop
End if

 

[JCel]

i.e only one time it should display "wrong username" after checking all records in DB...

 

[Robert_Zenz]

We can't tell you the solution, since we know nothing about your Database-Backend...especially what database it is. But you could execute a scalar command using the following query (which should apply to al SQL-Databases...I hope)

SELECT COUNT(*) FROM users WHERE username = 'username' AND password = 'password'

If the scalar returns 0, username of password is invalid, if it returns 1, then it's valid.

Bobby