How to extract all alphabet from a string containing alphanumeric in VB.NET

Question

0.00/5 (No votes)

See more:

Hi Guys, so i have a text box that the user will enter an alphanumeric code, however the database that i will use to store data will depend on the alphabet code ONLY inside this alphanumeric code. Can you help me how to start on this one please?

I.e. code entered on textbox1 is MSE001243, i need to extract the MSE and put it on a label that i can use to access the corresponding database.

Thankyou!

What I have tried:

I've seen seen validations but not extractions on the web :(

Posted 11-Nov-20 22:10pm

Member 14122214

Updated 11-Nov-20 22:55pm

Add a Solution

2 solutions

Solution 2

Use a regex:

VB

Dim input As String = "MSE001243, i need"
Dim output As String = Regex.Replace(input, "[^a-zA-Z]", "")

Posted 11-Nov-20 22:55pm

OriginalGriff

Comments

Sander Rossel 12-Nov-20 4:59am

"Some people, when confronted with a problem, think "I know, I'll use regular expressions." Now they have two problems." - Jamie Zawinski :)
A valid solution though.

OriginalGriff 12-Nov-20 5:29am

:D

Maciej Los 12-Nov-20 6:21am

5ed!

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Sander Rossel · Accepted Answer · 2020-11-11T22:54:00

Solution 1

You can loop through the chars in the string and use Char.IsLetter to check whether the character is a letter.
Using the Where extension and the String constructor that takes an array of Char, the code would look as follows.

VB

Dim letters = "MSE001243".Where(Function(c) Char.IsLetter(c)).ToArray()
Dim word = New String(letters)
' word is now MSE

Alternatively, you could use your pre-defined set of characters and use Contains instead.

VB

Dim allowed = "abcde...ABCDE..."
Dim letters = "MSE001243".Where(Function(c) allowed.Contains(c)).ToArray()

Posted 11-Nov-20 22:54pm

Sander Rossel

Updated 11-Nov-20 22:57pm

v2

Comments

Maciej Los 12-Nov-20 6:21am

5ed!

Member 14122214 13-Nov-20 3:26am

Dim letters = "MSE001243".Where(Function(c) Char.IsLetter(c)).ToArray()
Dim word = New String(letters)
' word is now MSE

this worked like a charm, how can i change "MSE001243" to textbox1.tex? i tried using

"& textbox1.text &".Where(Function(c) Char.IsLetter(c)).ToArray()

but it doesnt work as what i need is for the system to get the letter of whatever i type in textbox1.text

Member 14122214 13-Nov-20 3:39am

tried using this as well

 Dim sample As String = TextBox1.Text
        Dim letters = sample.Where(Function(c) Char.IsLetter(c)).ToArray()
        Dim word = New String(letters)
        Label3.Text = word

but also doesnt work

Sander Rossel 13-Nov-20 4:07am

This should work, assuming TextBox1 and Label3 are the correct TextBox and Label.
What doesn't work?
Do you get an error?

Member 14122214 15-Nov-20 20:34pm

sorry, i just missed callingmy private sub on the event haha.. all works now, thank you!

Sander Rossel 16-Nov-20 7:07am

Happens to the best of us! :)

Member 14122214 19-Nov-20 1:29am

sure does :D thanks!