How to find a repeated chain of chars in visual basic NET

Question

0.00/5 (No votes)

See more:

I have this piece of text in a RichTextBox:

RichTextBox1.Text = "ABCDEFTEST12ABCDEF"

How can I get the repeated string value "ABCDEF"?

edit: To be more specific, I need a "duplicate finder". This image should illustrate the plan: Image

What I have tried:

I have no idea how to resolve this issue.

Posted 15-Apr-17 9:40am

Member 11763983

Updated 15-Apr-17 14:05pm

v2

Add a Solution

Comments

Patrice T 15-Apr-17 15:59pm

Refine your question, I don't understand what you try to do.

Member 11763983 15-Apr-17 16:36pm

Is it clear now?

[no name] 15-Apr-17 17:30pm

No it isn't. We don't know what your homework assignment is. Are you checking for duplicate characters? Are you checking for duplicate words in a sentence? What did your teacher tell you to do? What were you studying in class?

Member 11763983 15-Apr-17 17:48pm

It's no homework and I'm not studying. I want to do this because I'm interested. I need a solution to find duplicate characters.

[no name] 15-Apr-17 18:28pm

If you do not study, how do you expect to learn? Study how to iterate through an array. Then learn how to ask questions. And get a book on programming and work though it.

Member 11763983 15-Apr-17 19:35pm

Do you know "learning by doing"? But ok, forget it, I will keep trying till I get a solution.

[no name] 16-Apr-17 8:30am

Yes I am very familiar with the concept. The problem is, you are not doing.

2 solutions

Solution 2

VB

Dim str() As String = {}
str = Split(RichTextBox1.Text, " ")
Dim str2 As String = ""
Dim str3() As String = {}
Dim duplicate_names As String = ""
Dim i As Integer = 1
For Each name As String In str
    str3 = Split(str2, " ")
    For Each name2 As String In str3
        If name = name2 Then
            If Not duplicate_names.Contains(name) Then
                duplicate_names += name & vbNewLine
                i += 1
            End If
        End If
    Next
    str2 += name & " "
Next
MsgBox(duplicate_names)

Posted 15-Apr-17 14:05pm

Member 11763983

Updated 15-Apr-17 23:20pm

v2

Comments

Ravi Bhavnani 15-Apr-17 20:15pm

Does your program work correctly with this text: BAND AND BAND? I would expect your program to identify "BAND" as the only duplicate word.

/ravi

Patrice T 15-Apr-17 20:45pm

Your code look wrong. As far as I understand "and band" and "band and" do not gibe same result.

Member 11763983 16-Apr-17 5:23am

Ya, it still don't work perfectly with "band and band".. but I let it be.

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)

Ravi Bhavnani · Accepted Answer · 2017-04-15T13:15:00

The answer lies in your question!

How can I get the repeated string value "ABCDEF"?

I think what you really meant was "how do I detect a repeated word in a bunch of text?"

The first step would be to break up the input text into a collection of words. Then, check for duplicate entries in the collection, perhaps by counting the occurences of each word. Words that occur more than once are your duplicates.

As you can see, I've broken your complex problem into two somewhat less complex problems. Your job now is to attack each of these problems and break them up into even simpler problems. This is called stepwise refinement and is at the core of software engineering - you break up a fairly abstract and complex task into a collection of simple and very well defined (and therefore programmable) tasks.

Some things that may help you achieve your goal are the String.Split() method[^] and the C# Dictionary[^] class which you can use to count occurences of each word you've discovered.

/ravi