I have a csv file having say 50 columns. its not always the case that all these column names are unique. so converting this in to a data table is not possible some times directly.
so my idea is ,
ignore column names and read csv
get first row (which are actually column names) .
convert it into a list of string .
find duplicates from this list. lets say i have 5 duplicates
below is the algorithm which will do the job , before that counter shuld be -1
for all dupe in duplicate items
{
for all str in string array
{
if (str is eq to dupe)
counter = counter + 1
if counter > 0
str = str + counter
}
}
Now write back in to the csv Row(0) with new string array.
then change the column names of the data table as Row(0) and now delete the first row.
i know this is extremely in-efficient. can some one suggest a better way ?
Instead of trying to find the duplicate column names just assign a number at the end of each field name. I used the TextFieldParser class. Available in Namespace: Microsoft.VisualBasic.FileIO See https://learn.microsoft.com/en-us/dotnet/api/microsoft.visualbasic.fileio.textfieldparser?view=netcore-3.1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim TFP As New TextFieldParser("C:\Users\maryo\Desktop\TestCSV.csv")
TFP.Delimiters = {","}
Dim FieldNames = TFP.ReadFields
For i = 0 To FieldNames.Length - 1
FieldNames(i) &= i.ToString
Next
Dim dt As New DataTable
For Each FieldName In FieldNames
dt.Columns.Add(FieldName)
Next
While Not TFP.EndOfData
Dim currentRow = TFP.ReadFields()
dt.Rows.Add(currentRow)
End While
DataGridView1.DataSource = dt
End Sub
Related
I have a textfile (data.txt) with 3 columns, each column with one variable (x1, x2 and x3). I would like to calculate a number of columns and show in a specific textbox (like textbox1).
For example. My data.txt:
x1 x2 x3
10 15 20
20 10 10
TextBox1 needs to show: 3
Text files don't have columns. What you have is a file where each line separates elements by a space and each row is separated by a CR/LF (carraige return/line feed) To work with the text file put
Imports System.IO
at the top of the code file.
I am guessing that you will want to do more with the file than just determin the number of "columns" so, we will read the entire file. File.ReadAllLines() returns an array of lines in the file.
We take the first line in the file (index 0) and split it by a space. The lowere case c followint " " tells the compiler that you mean a Char not a String. Then we take the Length of the resulting array to find the number of columns.
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim lines = File.ReadAllLines("C:\Users\******\Desktop\Code\OPdata.txt")
Dim NoOfColumns = lines(0).Split(" "c).Length
TextBox1.Text = NoOfColumns.ToString
'Some other things you can do
Dim dt As New DataTable
Dim columns = lines(0).Split(" "c)
dt.Columns.Add(columns(0), GetType(Integer))
dt.Columns.Add(columns(1), GetType(Integer))
dt.Columns.Add(columns(2), GetType(Integer))
For index = 1 To lines.Length - 1
Dim values = lines(index).Split(" "c)
dt.Rows.Add({values(0), values(1), values(2)})
Next
DataGridView1.DataSource = dt
End Sub
You might want to consider using Microsoft.VisualBasic.FileIO.TextFieldParser. It's designed to process structured text files (either delimited or fixed-width) and will remove some of the necessary ceremony compared with direct file I/O as in Mary's answer. Note that TextFieldParser implements IDisposable, so it should either be used within a Using block or disposed manually.
FileOpen(1, "data.txt", OpenMode.Input)
line1$ = LineInput(1) 'get first line
FileClose(1)
TextBox1.Text = UBound(Split(line1, " ")) + 1
...databox.text (from example code below) contains a large list of combined words(domain names) previously populated in the program. There is 1 per each line. In this example, it initially looks like:
thepeople.com
truehistory.com
workhorse.com
whatever.com
neverchange.com
...
The following code below saves the text inside databox to tlistfiltered.txt and then searches tlistfiltered.txt to retrieve all lines that contain any of the items in the list "arr()", and then populates listview(lv) with the results. This works just fine, but the results look like:
thepeople.com
truehistory.com
neverchange.com
...
but what I need is the "found string" (from arr()list to be Proper case so the result would be:
thePeople.com
trueHistory.com
neverChange.com
Here is the code....
Dim s As String = databox.Text
File.WriteAllText(dloc & "tlistfiltered.txt", s)
databox.Clear()
Dim text2() As String = System.IO.File.ReadAllLines(dloc & "tlistfiltered.txt")
Dim arr() As String = {"people", "history", "change"}
For index1 = 0 To arr.GetUpperBound(0)
Dim YesLines() As String = Array.FindAll(text2, Function(str As String)
Return str.Contains(arr(index1))
End Function).ToArray
databox.Visible = True
For index2 = 0 To YesLines.GetUpperBound(0)
Dim match As String = (YesLines(index2)) & vbCrLf
databox.AppendText(match)
Next
Next
s = databox.Text
File.WriteAllText(dloc & "tlistfilteredfinal.txt", s)
databox.Clear()
domains = (From line In File.ReadAllLines(dloc & "tlistfilteredfinal.txt") Select New ListViewItem(line.Split)).ToArray
lv.Items.Clear()
My.Computer.FileSystem.DeleteFile(dloc & "tlistfiltered.txt")
My.Computer.FileSystem.DeleteFile(dloc & "tlistfilteredfinal.txt")
BackgroundWorker1.RunWorkerAsync()
End Sub
Is there a way to do this on the fly? I have tried StrConv etc, but it will only convert the entire line to proper case. I only want the "found" word contained within the line to be converted....
edit:
after seeing #soohoonigan 's answer, i edited
databox.Visible = True
For index2 = 0 To YesLines.GetUpperBound(0)
Dim match As String = (YesLines(index2)) & vbCrLf
databox.AppendText(match)
Next
Next
to this:
databox.Visible = True
For index2 = 0 To YesLines.GetUpperBound(0)
Dim match As String = (YesLines(index2)) & vbCrLf
Dim myTI As System.Globalization.TextInfo = New System.Globalization.CultureInfo("en-US", False).TextInfo
If match.Contains(arr(index1)) Then
match = match.Replace(arr(index1), myTI.ToTitleCase(arr(index1)))
'StrConv(match, vbProperCase)
databox.AppendText(match)
End If
Next
and got the desired result!
Public Class Form1
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim test As String = "thepeople.com"
Dim search As String = "people"
Dim myTI As System.Globalization.TextInfo = New System.Globalization.CultureInfo("en-US", False).TextInfo
If test.Contains(search) Then
test = test.Replace(search, myTI.ToTitleCase(search))
MsgBox(test)
End If
Me.Close()
End Sub
End Class
I'm not sure to understand the need for using files for intermediate steps and deleting them at the end for example.
First step: getting the lines of the input
That can be done by using the Lines property of databox (which I suspect to be a TextBox or RichTextBox ; if it's not the case we can still use a Split on the Text property)
Dim lines = databox.Lines ' or databox.Text.Split({Environment.NewLine}, StringSplitOptions.RemoveEmptyEntries)
Second step: we want to filter those lines to keep only the ones containing the searched texts
For this there are several way, a simple one would be to use a Linq query to get the job done
Third step: transforming the result of the filter replacing the searched text by it's capitalized form
So we continue the started query and add a projection (or mapping) to do the transformation.
We need to use TextInfo.ToTitleCase for that.
' See soohoonigan answer if you need a different culture than the current one
Dim textInfo = System.Globalization.CultureInfo.CurrentCulture.TextInfo
Dim query = From word in arr
From line in lines
Where line.Contains(word)
Let transformed = line.Replace(word, textInfo.ToTitleCase(word))
select transformed
' We could omit the Let and do the Replace directly in the Select Clause
I tried searching and didn't have any success in fixing my problem so I tried finding my own solution.
First I found max (Max) value (min value is always 1), then I set loop to search value by value, but something is wrong with my loop.
For i As Integer = 1 To Max
For y As Integer = 0 To DataGridView1.Rows.Count - 1
If DataGridView1.Rows(y).Cells(0).Value = i Then
Else
builder2.Append(i & ",")
End If
Next
Next
To me loop looks OK but it's not working. If value i is found do nothing if it's not found add i to stringbuilder, and so on until it reaches Max value. But whatever combination I've tried I get some weird results.
Numbers are sorted from lowest to highest.
I've also extracted all values from DGV column to comma delimited string if it's easier that way...
EDIT :
Just for experimenting with that loop I've put i = 40 to 50 (to reduce the range). I know that missing values in DGV column are 40-46 and 59.
This is what I've got with loop above :
You can use LINQ to find missing numbers quite easily. You just need to get the existing numbers into a List, and then you can use Max() to find the largest number, and Except() to find the missing ones.
I put a DGV named DataGridView1 with one column, a button named bnPopulateDGV, and a button named bnFindMissingNumbers on a new Windows Form, and used the following code (with Option Infer On):
Private Sub bnPopulateDGV_Click(sender As Object, e As EventArgs) Handles bnPopulateDGV.Click
DataGridView1.Rows.Clear()
Dim seq1 = Enumerable.Range(1, 100).ToList()
Dim rand As New Random
' knock some out
For i = 1 To 5
seq1.RemoveAt(rand.Next(0, 50))
Next
For Each s In seq1
DataGridView1.Rows.Add(New String() {s.ToString()})
Next
End Sub
Private Sub bnFindMissingNumbers_Click(sender As Object, e As EventArgs) Handles bnFindMissingNumbers.Click
Dim existingNumbers As New List(Of Integer)
For Each r As DataGridViewRow In DataGridView1.Rows
existingNumbers.Add(CInt(r.Cells(0).Value))
Next
Dim min = 1
Dim max = existingNumbers.Max()
Dim missingNumbers = Enumerable.Range(min, max - min + 1).Except(existingNumbers)
MsgBox("Missing: " & String.Join(", ", missingNumbers))
End Sub
I have a table named users which has the following columns in it
User_id,user_name,user_pwd,First_Name,Middle_Name,Last_Name and user_type.
I have dataset named dst and created a table called user in the dataset. Now I want to populate listbox with user_Name, First_Name, Last_name of each and every row in the table user.
I am able to add one column value at a time but not getting how to add multiple column values of each row to listbox
Dim dt As DataTable = Dst.Tables("user")
For Each row As DataRow In dt.Rows
lstUsers.Items.Add(row("User_Name"))
Next
Above code works perfectly but I also want to add First_name as well as last_name to the list box at the same time.
Use same approach as you have, but put all values you want in one string.
Dim dt As DataTable = Dst.Tables("user")
For Each row As DataRow In dt.Rows
Dim sItemTemp as String
sItemTemp = String.Format("{0},{1},{2}", row("User_Name"), row("First_Name"), row("Last_Name"))
lstUsers.Items.Add(sItemTemp)
Next
String.Format() function will call .ToString() on all parameters.
In this case if row(ColumnName) is NULL value then .ToString() return just empty string
You have 2 choices:
Using the ListBox:
To use the ListBox, set the font to one that is fixed width like courier new (so that the columns line up), and add the items like this:
For Each row As DataRow In dt.Rows
lstUsers.Items.Add(RPAD(row("User_Name"),16) & RPAD(row("First_Name"),16) & RPAD(row("Last_Name"),16))
Next
The RPAD function is defined like this:
Function RPAD(a As Object, LENGTH As Object) As String
Dim X As Object
X = Len(a)
If (X >= LENGTH) Then
RPAD = a : Exit Function
End If
RPAD = a & Space(LENGTH - X)
End Function
Adjust the LENGTH argument as desired in your case. Add one more for at least one space. This solution is less than ideal because you have to hard-code the column widths.
Use a DataGridView control instead of a ListBox. This is really the best option, and if you need, you can even have it behave like a ListBox by setting the option to select the full row and setting CellBorderStyle to SingleHorizontal. Define the columns in the designer, but no need to set the widths - the columns can auto-size, and I set that option in the code below. if you still prefer to set the widths, comment out the AutoSizeColumnsMode line.
The code to set up the grid and add the rows goes like this:
g.Rows.Clear() ' some of the below options are also cleared, so we set them again
g.AutoSizeColumnsMode = DataGridViewAutoSizeColumnMode.AllCells
g.CellBorderStyle = DataGridViewCellBorderStyle.SingleHorizontal
g.SelectionMode = DataGridViewSelectionMode.FullRowSelect
g.AllowUserToAddRows = False
g.AllowUserToDeleteRows = False
g.AllowUserToOrderColumns = True
For Each row As DataRow In dt.Rows
g.Rows.Add(row("User_Name"), row("First_Name"), row("Last_Name"))
Next
You might solved your problem by now but other users like me might have issue with it.
Above answers given worked for me even but I found a same answer in a simple way according to what I want..
cmd = New SqlCommand("select User_Name, First_Name, Last_Name from User")
Dim dr As SqlDataReader = cmd.ExecuteReader(YourConnectionString)
If dr.HasRows Then
Do While dr.Read
lst.Items.Add(dr.Item(0).ToString & " " & dr.Item(1).ToString & " " & dr.Item(2).ToString)
Loop
End If
This worked for me, maybe wrong way but I found it simple :)
May I suggest you use a ListView control instead of Listbox?
If you make the switch, here's a sample subroutine you could use to fill it up with the data you said you want. Adapt it the way you like; there's much room for improvement but you get the general idea:
Public Sub FillUserListView(lstUsers As ListView, Dst As DataSet)
Dim columnsWanted As List(Of String) = New List(Of String)({"User_Name", "First_Name", "Last_Name"})
Dim dt As DataTable = Dst.Tables("user")
Dim columns As Integer = 0
Dim totalColumns = 0
Dim rows As Integer = dt.Rows.Count
'Set the column titles
For Each column As DataColumn In dt.Columns
If columnsWanted.Contains(column.ColumnName) Then
lstUsers.Columns.Add(column.ColumnName)
columns = columns + 1
End If
totalColumns = totalColumns + 1
Next
Dim rowObjects(columns - 1) As ListViewItem
Dim actualColumn As Integer = 0
'Load up the rows of actual data into the ListView
For row = 0 To rows - 1
For column = 0 To totalColumns - 1
If columnsWanted.Contains(dt.Columns(column).ColumnName) Then
If actualColumn = 0 Then
rowObjects(row) = New ListViewItem()
rowObjects(row).SubItems(actualColumn).Text = dt.Rows(row).Item(actualColumn)
Else
rowObjects(row).SubItems.Add(dt.Rows(row).Item(actualColumn))
End If
lstUsers.Columns.Item(actualColumn).Width = -2 'Set auto-width
actualColumn = actualColumn + 1
End If
Next
lstUsers.Items.Add(rowObjects(row))
Next
lstUsers.View = View.Details 'Causes each item to appear on a separate line arranged in columns
End Sub
I created a custom GridView (actually a RadGrid) which does roughly the following.
Initialize GridView formatting
Setup Columns (depending on type of data to be displayed)
Populate the rows
When Instantiating this GridView, and adding it to my page, I want the first column to contain a "rowspan" attribute on the first row of repeated, but similar data. The "rowspan" value should be equal to the number of similar rows following it. In this way I hope to make the final view cleaner.
The logic for this, I figure, should take place while populating the rows. Initially I add rows to a DataTable and then bind it to the GridView as the final step.
Here's the general logic I was attempting, but it didn't work for me. What am I doing wrong?
Dim dt As New DataTable() 'Has three default columns
For Each d In Documents 'MAIN ITEM (First Column Data)
Dim rowspan As Integer
rowspan = 0
For Each f In Files
If rowspan = 0 Then
Me.dt.Rows.Add(New Object() {d.Title, f.Language, f.FileSize})
'THIS DOESN'T WORK!
Me.dt.Columns(0).ExtendedProperties.Item("rowspan") = rowspan.ToString()
Else
Me.dt.Rows.Add(New Object() {Nothing, f.Language, f.FileSize})
End If
rowspan += 1
Next
Next
Also keep in mind that the this is dumped into a DataView which is sorted by the first column, so I would imagine it must actually be sorted first, then somehow count the rows for each "like" first column, then set the "rowspan" value for the first row of that column equal to the number of rows belonging to it.
Does this make sense? Here is an ideal example of what I would like to accomplish in the layout:
Try this.
Protected Sub DemoGrid_PreRender(sender As Object, e As System.EventArgs) Handles DemoGrid.PreRender
MergeRowsWithSameContent(sender)
End Sub
Public Sub MergeRowsWithSameContent(gvw As GridView)
For rowIndex As Integer = gvw.Rows.Count - 2 To 0 Step -1
Dim row As GridViewRow = gvw.Rows(rowIndex)
Dim previousRow As GridViewRow = gvw.Rows(rowIndex + 1)
For i As Integer = 0 To row.Cells.Count - 1
If row.Cells(i).Text = previousRow.Cells(i).Text Then
row.Cells(i).RowSpan = If(previousRow.Cells(i).RowSpan < 2, 2, previousRow.Cells(i).RowSpan + 1)
previousRow.Cells(i).Visible = False
End If
Next
Next
End Sub
P.S: Shameless port of this wonderful code I have been using for years.