How do I, dictionary(of integer, list(of integer)) to string with linq and string.join method?

Question

0.00/5 (No votes)

See more:

I have a Dictionary

Dim DicInt As New Dictionary(Of Integer, List(Of Integer))
DicInt.Add(5, {4, 5, 3}.ToList)
DicInt.Add(6, {8, 1}.ToList)

How can i get string like this

5 > 4,5,3
6 > 8,1

Thanks.

What I have tried:

Dim strSutun2 As String = String.Join(vbNewLine, String.Join(" > ", DicInt.Select(Function(list) String.Join(",", list))))

Posted 15-Nov-19 3:13am

gacar

Updated 10-Dec-19 12:32pm

v3

Add a Solution

Comments

[no name] 15-Nov-19 11:06am

A foreach loop on the dictionary key would be easier (to understand).

LINQ isn't going to be "faster".

gacar 15-Nov-19 11:24am

Contrary to popular belief, the linq method is not very slow. At least from what I saw in my own programs. It is also tempting that the code is simple.

phil.o 15-Nov-19 11:40am

What is the outcome of the code snippet you provided?

gacar 15-Nov-19 11:48am

I had this: [5, System.Collections.Generic.List`1[System.Int32]] > [6, System.Collections.Generic.List`1[System.Int32]]

phil.o 15-Nov-19 12:04pm

Why not trying to create an extension method to a Dictionary(of T, List(of U)) first? Then, if you really want to use Linq for that, you could try to translate it.

gacar 15-Nov-19 12:21pm

How can i do that, i dont know. I am not well coder, i am an amateur.

phil.o 15-Nov-19 13:27pm

Well, to be honest I stopped VB.NET when generics did not exist yet. I could write that down in C# in a matter of minutes.
I'll try to come up with something usable (but I have to eat first; about 1hr delay).

gacar 15-Nov-19 13:30pm

Thank you. I can convert c# to vb.net

3 solutions

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)

phil.o · Accepted Answer · 2019-11-15T07:50:00

Solution 1

Here you are for the C# version.

C#

using System.Collections.Generic;
using System.Text;

// You need a static class for extension methods.
public static class DictionaryExtensions
{
   public static string Dump<T, U>(this IDictionary<T, IList<U>> dictionary)
   {
      StringBuilder builder = new StringBuilder();
      string newline = Environment.NewLine;
      int length = newline.Length;
      foreach (var pair in dictionary)
      {
         builder.AppendFormat
         (
            "{0} > {1}",
            pair.Key,
            string.Join(",", pair.Value)
         );
         builder.Append(Environment.NewLine);
      }
      builder.Remove(builder.Length - length, length); // Remove last line feed
      return builder.ToString();
   }
}

Usage:

VB.NET

Dim strSutun2 As String = DicInt.Dump()

Hope this helps.

Posted 15-Nov-19 7:50am

phil.o

Comments

gacar 15-Nov-19 13:59pm

Thank you for your solution.

gacar 15-Nov-19 14:12pm

I converted code. But i couldnt call. How can i call in vb?

Imports System.Collections.Generic
Imports System.Text
Imports System.Runtime.CompilerServices
Module DictionaryExtensions
<extension()>
Function Dump(Of T, U)(ByVal dictionary As IDictionary(Of T, IList(Of U))) As String
Dim builder As StringBuilder = New StringBuilder()
Dim newline As String = Environment.NewLine
Dim length As Integer = newline.Length

For Each pair In dictionary
builder.AppendFormat("{0} > {1}", pair.Key, String.Join(",", pair.Value))
builder.Append(Environment.NewLine)
Next

builder.Remove(builder.Length - length, length)
Return builder.ToString()
End Function
End Module

gacar 15-Nov-19 14:14pm

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim DicInt As New Dictionary(Of Integer, List(Of Integer))
DicInt.Add(5, {4, 5, 3}.ToList)
DicInt.Add(6, {8, 1}.ToList)

Dim strSutun2x As String = DicInt.Dump() 'Here error occured
End Sub

phil.o 15-Nov-19 14:34pm

Have you tried Imports DictionaryExtensions at the beginning of your form code?

gacar 15-Nov-19 14:45pm

I imported but i have this error still :
"Error BC30456 'Dump' is not a member of 'Dictionary(Of Integer, List(Of Integer))'.

phil.o 15-Nov-19 14:49pm

This suggests that you did not import properly. Maybe a namespace issue? I cannot do better than guessing I'm afraid...

Maciej Los · Accepted Answer · 2019-11-15T11:21:00

Solution 2

Try this:

VB.NET

Dim DicInt As New Dictionary(Of Integer, List(Of Integer))
DicInt.Add(5, New List(Of Integer) From {4, 5, 3})
DicInt.Add(6, New List(Of Integer) From {8, 1})


Dim result = DicInt _
    .Select(Function(kvp) _
        String.Concat(kvp.Key, " => ", _
            String.Join(", ", kvp.Value.Select(Function(x) x)))) _
    .ToList()
For Each s As String In result
	Console.WriteLine(s)
Next

Posted 15-Nov-19 11:21am

Maciej Los

Comments

gacar 15-Nov-19 19:26pm

Thanks for solution.

Maciej Los 16-Nov-19 1:48am

You're very welcome.

Maciej Los 18-Nov-19 5:17am

Can you accept this answer as a solution? This should be done to remove your question from unanswered list. Use green button.

gacar · Accepted Answer · 2019-12-10T12:33:00

Solution 3

I found this solution.

VB

Dim str As String = String.Join(vbNewLine, DicInt.Select(Function(x) x.Key & " > " & String.Join(",", x.Value)))

Result:
5 > 4,5,3
6 > 8,1

Posted 10-Dec-19 12:33pm

gacar

Updated 10-Dec-19 12:53pm

v4