Loops

[grw]

Hi there,
I am quite new to VB and I am trying to write a loop in my program that allows you to have five attempts in getting the password correct, after which it will exit you.
Can someone please show me how this can be done using:
1) Do-While loop.
2) For loop.
3) Any other method
Any help will be appreciated.
Thank you in advance.
I have included below the code that I have been trying to use, but it does not work.

Private Sub CmdValid_Click()
'This procedure checks the input password
Dim Response As Integer
Do
If txtPassword.Text = txtPassword.Tag Then
'If correct, display message box
MsgBox "You've passed security!", vbOKOnly + vbExclamation, "Access Granted"

Else
'If incorrect, give option to try again
Response = MsgBox("Incorrect password", vbRetryCancel + vbCritical, "Access Denied")
End If
If Response = vbRetry Then

txtPassword.SelStart = 0
txtPassword.SelLength = Len(txtPassword.Text)

Response = Response + 1
lblCounter.Caption = Response
Print Response
Else
End
End If
txtPassword.SetFocus

Loop While Response < 5
End Sub

[andyleno]

'Dim numTries as long

private Sub Form_Load()
numTries = 1
End Sub

private Sub CmdValid_Click()
If numTries = 5 then
MsgBox "You have Exceeded to amount of attempts allocated", vbOKOnly, App.Title
Exit Sub
End If
'This procedure checks the input password
Dim Response as Integer

If txtPassword.Text = txtPassword.Tag then
'If correct, display message box
MsgBox "You've passed security!", vbOKOnly + vbExclamation, "Access Granted"

else
'If incorrect, give option to try again
Response = MsgBox("Incorrect password", vbRetryCancel + vbCritical, "Access Denied")
End If
If Response = vbRetry then
numTries = numTries + 1
txtPassword.SelStart = 0
txtPassword.SelLength = len(txtPassword.Text)

Response = Response + 1
lblCounter.Caption = Response
print Response
else
End
End If
txtPassword.SetFocus

End Sub




Andy

Don't forget to rate!!!!

Andrew Lennon (Berlitz)
Automation Dev Engineer

[V.B.For Dummie's]

To be quite honest , only 1 attempt is needed.If a user purchased a product then they will type in the correct password the first time.By allowing any type of limit....3 try's ,4,5,etc..... you are really just putting a hole into your security.I would have the application unload on the first failure .Without using any message boxes.If you use a message box then it will show it in the assembly code and pinpoint a cracker closer to the required offset that will allow them to change your preset limit of password attempt's and then they will be able to run their password generator's on your program.This is just my opinion.P.S. the program"VBde085" will tell any and all message boxes used as well as what the message box say's in an .Exe and will show the coresponding offset's , as well as other information .To fool a cracker , just place a bunch of B.S. "If" statement's.These statement's are quickly found in assembly code by looking for "0F85" (which mean's Jump if condition is met), the cracker look's for this piece of code and changes it to "0F84" (which mean's "Jump if condition is not met).This is a minor technique used to at least make the cracker would be.... spend the next year tracing through all the "If" statement's,by then your product would either be outdated , or already up-graded.

Regard's,
Danny
http://www.geocities.com/wildthing40486/Xara.html

[DSJ]

That's strange because I compiled this

option Explicit

private Sub Main()
Dim iVar as Integer
iVar = CInt(Command)
If 1 = iVar then
MsgBox "1 = " & iVar
End If
If 2 = iVar then
MsgBox "2 = " & iVar
End If
If 3 = iVar then
MsgBox "3 = " & iVar
End If
If 4 = iVar then
MsgBox "4 = " & iVar
End If
If 5 = iVar then
MsgBox "5 = " & iVar
End If
If 6 = iVar then
MsgBox "6 = " & iVar
End If
End Sub




and the EXE doesn't have a single 0F85 OR 0F84 in it...???

[V.B.For Dummie's]

did you do a search ? . the 0F85 is only one jump statement though. there are several of them actually.On the line of assembly that has this statement (JNB,JNE,,etc...) , look to the left , you see that long line of numbers? anyway's, the jump statement's are there.Conditional jump if codition is met.I use w32dsm89 , personally , along with Hackman 6.01., HexWorkshop ,and vbde085.This is just my personal opinion.I would rather a cracker search through all the conditional jump if's and make them really work for my program.When you use the "vbde085"It will give you the address,code offset of any message boxes used , this is what one would use to narrow their search to the correct Jump statement.
Here are just a couple of Jump statements that are in assembly, theres lot's more . The 0F85 was just one of them
JA
JAE
JB
JBE
JC

Regard's,
Danny
http://www.geocities.com/wildthing40486/Xara.html