C# / Filter input of a textbox and display notification balloon

Posted by asmo on Stack Overflow See other posts from Stack Overflow or by asmo
Published on 2011-02-22T23:12:15Z Indexed on 2011/02/22 23:24 UTC
Read the original article Hit count: 355

Filed under:

c#

|

input

|

textbox

|

filter

|

notifications

I'm wondering how to filter the input of a .NET textbox.

I already know that I could listen for the KeyDown event and intercept the key, but that won't filter pasted strings by a right-click menu or a CTRL+V.

I also don't wan't to completely disable the possibility of pasting of characters in the textbox. The paste action should be cancelled whenever it contains one or more invalid characters.

Finally, I'd like to display a notification balloon whenever invalid characters are either entered or pasted.

µTorrent already has this exact behavior:

enter image description here

How can I achieve this functionality in C# ?

© Stack Overflow or respective owner

Related posts about c#

.NET WebRequest.PreAuthenticate not quite what it sounds like

as seen on West-Wind - Search for 'West-Wind'
I’ve run into the problem a few times now: How to pre-authenticate .NET WebRequest calls doing an HTTP call to the server – essentially send authentication credentials on the very first request instead of waiting for a server challenge first? At first glance this sound like it should be easy:… >>> More
HttpWebRequest and Ignoring SSL Certificate Errors

as seen on West-Wind - Search for 'West-Wind'
Man I can't believe this. I'm still mucking around with OFX servers and it drives me absolutely crazy how some these servers are just so unbelievably misconfigured. I've recently hit three different 3 major brokerages which fail HTTP validation with bad or corrupt certificates at least according to… >>> More
The dynamic Type in C# Simplifies COM Member Access from Visual FoxPro

as seen on West-Wind - Search for 'West-Wind'
I’ve written quite a bit about Visual FoxPro interoperating with .NET in the past both for ASP.NET interacting with Visual FoxPro COM objects as well as Visual FoxPro calling into .NET code via COM Interop. COM Interop with Visual FoxPro has a number of problems but one of them at least got a lot… >>> More
Dynamic Type to do away with Reflection

as seen on West-Wind - Search for 'West-Wind'
The dynamic type in C# 4.0 is a welcome addition to the language. One thing I’ve been doing a lot with it is to remove explicit Reflection code that’s often necessary when you ‘dynamically’ need to walk and object hierarchy. In the past I’ve had a number of ReflectionUtils that used string based expressions… >>> More
Finding a Relative Path in .NET

as seen on West-Wind - Search for 'West-Wind'
Here’s a nice and simple path utility that I’ve needed in a number of applications: I need to find a relative path based on a base path. So if I’m working in a folder called c:\temp\templates\ and I want to find a relative path for c:\temp\templates\subdir\test.txt I want to receive back subdir\test… >>> More

Related posts about input

Twitter Bootstrap styling conflicts with plug-ins like jqGrid and other third part libraries

as seen on Geeks with Blogs - Search for 'Geeks with Blogs'
Issues:The concern is that the Twitter Bootstrap framework is that some of their css selectors are simply too generic and have incompatibility issues and conflicts with most third party plug-ins and css libraries, like jQuery-UI and jqGrid.My most pressing concern is only with the generic selector… >>> More
HTML text input and using the input as a variable in a script(tcl)/sql(sqlite)

as seen on Stack Overflow - Search for 'Stack Overflow'
Hello all, I'm very VERY new at this whole web thing. And I'm just very confused in general. Basically, what I want to do is take an input via text using HTML and adding that input to database, table trans. Should be simple but I am lost. <li>Transaction Number</li> <li><input… >>> More
A quiz with results

as seen on Programmers - Search for 'Programmers'
I'm currently working on programming a quiz withe results. I've tried this: <html> <body> <h1></h1> <form> <ol> <li> How much are you willing to spend on a phone per month?</li> <ul> <li><input type = "radio" name = "q1" id="q1_1">… >>> More
How to change SMP affinity of an IRQ on Ubuntu domU inside Xen XCP?

as seen on Server Fault - Search for 'Server Fault'
I'd like to change IRQ SMP affinity for reasons, outlined in this question: CPU0 is swamped with eth1 interrupts But I can't — I see Input/output error when I try to write to /proc/irq/*/smp_affinity. Please point me to the HOWTO on the matter. (A formal reference on /proc/irq/*/ would be cool as… >>> More
How do I fix a corrupted harddrive after failed upgrade?

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
The problem originated when I was trying to fix this problem. Things went horribly, horribly wrong and I ended up with a new problem altogether. The last thing I did was run sudo apt-get install and that caused my system to freeze. I restarted my computer and it would not boot from the harddrive… >>> More