How to restrict the copy & paste in string control?

[Kumar_B]

In my application user name & password string controls are there.After typing the username in string control it is copied and paste it in password string control .

I like to restrict the string copy from one string control  & paste it into another string control ?

How to do this?

Kumar.

[smercurio_fc]

OK, I've got to ask: why in the world would you want to do this? As a user, if I was using an application that did this, I'd find the developer and hit them. Why? Because you're violating basic user interface principles.

[Nadim R]

Hi Kumar,

One easy way to copy data from one control to another is to use a local variable.  Simply right click Password and click create>>local variable.  Wire that local variable to the Username.


Regards,

Nadim R
Applications Engineering
National Instruments

[smercurio_fc]

Yes, but I was questioning the poster's apparent need to restricting being able to copy and paste from one string control to another. I was very curious as to why he believes this is a necessary user interface "feature".

[Ben]

These images illustrate anoth approach to inhibit the copying of text which is available in LV 8.2 (maybe 8.0)

Ben

Message Edited by Ben on 12-07-2006 10:12 AM

[Will.D]

@ smercurio_fc

This is a perfectly viable UI "change".  You'll find in most secure applications/websites that you are not allowed to paste into a password box.  Try it next time you log into Windows (assuming you use it).

[TCPlomp]

Well in windows you can post into the password box.

We used this once, on a system that was in the field, we found that the new user had a password duration off 14 days....
On site we only had a USB-mouse to connect. When the system booted, it prompted for a new password (the original password was saved using for auto-logon), the only thing we could do was copy and paste.
It saved my ass.

Ton

[Enrique]

I don't understand the original question. You want to deny the ability to paste something into the password field?

I don't see the security of this. I hope you are not automatically writing the password into the password field once the user writes the username. You do want to make sure the password field is erased once you hit OK.

[TCPlomp]

What you could do is wait on a key down /mouse down event (first key OR paste), note the timestamp, and wait on the value change event (or the OK button). If this is to soon after each other (> 10 chars/second) you could flush the input.

Ton

[chrisger]

...or you could wait for the "Mouse enter" event of the password control and then clear the clipboard. or you compare the password with the clipboard contents and deny logon if they are identical.  there are VIs for clipboard handling with LV8.x.