[RESOLVED] Swap words in a string

[chathu1234]

i want to write a code to swap the words in a string.
Input - I like cake
Output - cake I like

To do this it would be great if there is a way to determine the index of each word.Like
1- I
2- like
3- cake
Then I can swap the words.But I have no idea how to do it.
Currently I have written the code to count the number of words in a string and to get the average.

 Dim str As String = Me.t1.Text

        Dim strA() As String = str.Split(" ")

        Dim TChrs As Int32

        Dim i As Int32

        For i = strA.Length - 1 To 0 Step -1

            TChrs += strA(i).Length

        Next

        MsgBox("Number of words = " & strA.Length)

        MsgBox("Average Length = " & TChrs / strA.Length)

Can any one please help me with this

[Hack]

Do you always want the last word in the string to be the first word in the string after the swap?

[chathu1234]

Do you always want the last word in the string to be the first word in the string after the swap?

Thank you sir for replying!
No I dont always want that to happen. Actually I am trying to build a search method for database records.So I want to search names.If someone search for "Chandler Muriel Bing" ,then the application should search for "Chandler Muriel Bing" , "Chandler Bing Muriel" , "Muriel Bing Chandler" , "Muriel Chandler Bing" , "Bing Chandler Muriel" and "Bing Muriel Chandler".
Thats the idea.
It will be so helpful if you could help me in anyway.

Thank you

[Hack]

Why not just use the SQL LIKE keyword. If you do

SELECT whatever, whatever, whatever
FROM table
WHERE username 
LIKE '%Chandler%'

This would pull all names that had Chandler in it regardless of where it was or how many names there were in that field.

[chathu1234]

Why not just use the SQL LIKE keyword. If you do

SELECT whatever, whatever, whatever
FROM table
WHERE username 
LIKE '%Chandler%'

This would pull all names that had Chandler in it regardless of where it was or how many names there were in that field.

I have already tried that.This is a sample of my current code

Private Sub txtProperty_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles txt.TextChanged
        Dim s As String = Me.txt.Text
        For i As Integer = s.Length - 1 To 1 Step -1
            s = s.Insert(i, "%")
        Next

        Dim w_to_v As String = Replace(s, "w", "[wv]")
        Dim v_to_w As String = Replace(s, "v", "[wv]")

        Dim constr As String = "Provider=Microsoft.ACE.OLEDB.12.0;DataSource=E:\Band6_2011-10-01.mdb;Jet OLEDB:Database Password=3rdband"
        Dim con As OleDbConnection = New OleDbConnection(constr)

        If Me.txt2.Text = "" And Me.txt.Text <> "" Then
            Dim da As OleDbDataAdapter = New OleDbDataAdapter("SELECT Indv_NAME As [Name in NIC] from tbl_Indv INNER JOIN tbl_householdinfo ON tbl_Indv.UNIQUE_ID = tbl_householdinfo.UNIQUE_ID where (Indv_NAME Like '%" & w_to_v & "%' or Indv_NAME Like '%" & v_to_w & "%' )", con)

 Dim ds As New DataSet()
            'fill the datset
            da.Fill(ds)
            'attach dataset to the datagrid
            DataGridView1.DataSource = ds.Tables(0)
            ds = Nothing
            da = Nothing
            con.Close()
            con.Dispose(
         End sub

This will give a pretty good result.But with this code there is a problem.
Lets say there is an entry named "Bing Chandler".If we search for "Chandler Bing" for some reason the data grid is emptied.
If I search for Chandler or Bing separately then i will get the record.
Do you know what the reason might be?
Is it because i have it in a textchanged method?

[Hack]

Lets say there is an entry named "Bing Chandler".If we search for "Chandler Bing" for some reason the data grid is emptied.
If I search for Chandler or Bing separately then i will get the record.

That makes perfect sense. That is how the LIKE keyword works.

Do you know what the reason might be?

See above

Why the need for the JOIN? What happens if you just do

"SELECT Indv_NAME As [Name in NIC] 
from tbl_Indv 
where Indv_NAME 
Like '%" & w_to_v & "%' 
or 
Indv_NAME Like '%" & v_to_w & "%' "

[chathu1234]

Sorry about the JOIN.It was to get a value from the other table.
Why the above code wont work for me is that I want to find people with a certain name.But I have a database with over 8,00,000 names and they are Sinhala(Sri Lankan) names and very easily misspelled.
The above code helps me with the misspeling thing but I cant find the person named "Ranjit Fernando" if the user search for "Fernando Ranjit"
But the user can search for "ranjt frnnd" or "ranjithhh ferrrrnandoaa" or whatever but cant search if the names are swapped.
I learnt VB on my own so I dont know methodical explanation for this issue.

I have written a code just now which will swap two words in a string.

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim str As String = Me.t1.Text

        Dim strA() As String = str.Split(" ")

        Dim ne(100) As String
        ne(0) = strA(1)
        ne(1) = strA(0)

        MessageBox.Show(ne(0) + " " + ne(1))

    End Sub

this works perfectly.But its for two words.Can you help me implement this code for any number of words?

Thank you

[SeanGrebey]

Use strA.Length - 1 to find the index of the last word instead of assuming 1.

[Hack]

Quick example. This is using a fixed string for testing purposes. You will need to change "I like oat meal cookies" to the name of the field containing all the names. First, store them in an array and just iterate through them adding an OR to your SELECT clause each iteration.

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim sString As String = "I love oat meal cookies"
        Dim sLIKEClause As String = String.Empty
        Dim arrString() As String = Split(sString, " ")
        sLIKEClause = "LIKE Indv_NAME = '%" & arrString(0).ToString & "%' "
        For i As Integer = 0 To arrString.Length - 1
            sLIKEClause = sLIKEClause & " OR Indv_NAME LIKE '%" & arrString(i).ToString & "%' "
        Next
        MessageBox.Show(sLIKEClause)
    End Sub

You would then take that string (sLikeClause) and add it to your SQL

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim sString As String = "I love oat meal cookies"
        Dim sLIKEClause As String = String.Empty
        Dim arrString() As String = Split(sString, " ")
        sLIKEClause = "LIKE fieldname '%" & arrString(0).ToString & "%' "
        For i As Integer = 0 To arrString.Length - 1
            sLIKEClause = sLIKEClause & " OR fieldname LIKE '%" & arrString(i).ToString & "%' "
        Next
        Dim sql As String = "SELECT Indv_NAME As [Name in NIC] "
        sql = sql & "from(tbl_Indv) "
        sql = sql & "where Indv_NAME " & sLIKEClause
        MessageBox.Show(sql)
End Sub

[chathu1234]

Dear Hack

This is a fabulous idea and it works like charm.Im so thankful to you for taking your time out to help me with this code.
While enjoying your code the only issue I got was that now I get a huge number of results in the recordset and its not what I really want.
Is there a way to append those words differently and then search again?
Ex: I love oat meal cookies
I love
I oat
I meal
....
oat cookies

You get the idea.
Im so sorry for troubling you with a code which might not make sense to someone else but its really important that I figure this out.

Hope you could help more

Thank you

[chathu1234]

Use strA.Length - 1 to find the index of the last word instead of assuming 1.

Thank you sir for replying

I already have a code written to get the last three words of a string and jumble the words in one way.

Dim str As String = Me.t1.Text

        Dim strA() As String = str.Split(" ")

        If strA.Length > 2 Then
            Dim a As String = (strA(strA.Length - 3) + " " + strA(strA.Length - 2) + " " + strA(strA.Length - 1))
            Dim a2() As String = a.Split(" ")
            Dim ne(100) As String
            ne(0) = a2(1)
            ne(1) = a2(2)
            ne(2) = a2(0)
            MessageBox.Show(ne(0) + " " + ne(1) + " " + ne(2))
        End If

I know it is not a very good code.Pardon my coding knowledge.
I want a code that does the above procedure no matter how many words are entered.I want to get the maximum number of results.Like with 3 words I should get 6 possible strings

[SeanGrebey]

Where you are doing this:

            Dim ne(100) As String
            ne(0) = a2(1)
            ne(1) = a2(2)
            ne(2) = a2(0)
            MessageBox.Show(ne(0) + " " + ne(1) + " " + ne(2))

Do loops instead:

For intI as integer = 0 to a2.Length - 2
  ne(intI) = a2(intI+1)
Next

' Get the last one
ne(a2.Length - 1) = a2(0)

Dim strOutput as String

For intI as integer = 0 to a2.Length - 1
  strOutput = strOutput  + ne(intI) + " " 
Next

' SHow and remove trailign space
MessageBox.Show(Trim(strOutput))

That's just quick and dirty, can probably be cleaned up, but you get the idea.

[chathu1234]

Dear Hack and Sean

Thank you both for taking your time and suggesting ways to find a solution for my case.I really appreciate it.
I have finally found a method which will give all the possible permutations for combinations of words in a string.Hers is the code I found.And all the credit should go to a gentlemen named LanFanNinja.He used Heap's alogorithm for this.

Private Sub Form1_Load(sender As Object, e As EventArgs)
    Dim word As String = "I like cake"
    Dim split As String() = word.Split(New Char() {" "c}, 
        StringSplitOptions.RemoveEmptyEntries)
    Dim words As New List(Of String)()
 
    HeapPermute(words, split, split.Length)
 
    ' "words" now contains all possible permutations of "word"
End Sub
 
Private Sub HeapPermute(words As List(Of String), split As String(), splitCount As Integer)
    Dim n As Integer = splitCount
 
    If n = 1 Then
        'add item
        Dim temp As String = ""
        For i As Integer = 0 To split.Length - 1
            temp += split(i) & " "
        Next
        words.Add(temp.TrimEnd(" "c))
    Else
        For i As Integer = 0 To n - 1
            HeapPermute(words, split, (n - 1))
            If n Mod 2 = 1 Then
                'odd
                Dim temp As String = split(0)
                split(0) = split(n - 1)
                split(n - 1) = temp
            Else
                'even
                Dim temp As String = split(i)
                split(i) = split(n - 1)
                split(n - 1) = temp
            End If
        Next
    End If
End Sub

This code will provide this outcome

I like cake
like I cake
cake I like
I cake like
like cake I
cake like I

If you can please suggest any improvements.

Thank you