i'm having problems on how to display continuously with for loop statement, what i want it to display with be data1, data2, data3, data4 and so on with a comma and single space on each value. here's what i do :
Dim str
For i = 0 To FuelPrice.Items.Count - 1
str = FuelPrice.Items(i).SubItems(0).Text
MsgBox(str & ", ")
Next
but i did not get what i expect..lol sorry for the noob question though for i am just totally a noob..lol thanks in advance
Use a StringBuilder to accumulate your text in a single buffer and then display it outside the loop
Dim str as StringBuilder = new StringBuilder()
For i = 0 To FuelPrice.Items.Count - 1
str.Append(FuelPrice.Items(i).SubItems(0).Text & ", ")
Next
' To remove the comma added at the end
if str.Length > 0 then
str.Length -= 1
End If
MsgBox(str.ToString())
You can also use a generic list (or an array if you prefer), then concatenate the result together. I think this code is cleaner.
Imports System.Collections.Generic ' If not already referenced
Dim str As New List(Of String)
For i = 0 To FuelPrice.Items.Count - 1
str.Add(FuelPrice.Items(i).SubItems(0).Text)
Next
MsgBox(String.Join(", ", str))
Related
okay so i have two textboxes for user input, and i need help storing these into a single two dimensional array.
for 49 columns and two rows (states, capitals)
i already declared the array to:
Dim states(49,1) as string
states(0,0)= textbox1.text
states(0,1) = textbox2.text
im not sure what else to do because i have
am i storing this right? im not sure what more to do to store the rest of input into the array.
any help would be appreciated. thank you!
Declare module/class scope variables:
Dim states(49,1) as string
Dim nextInd as Integer = 0
Then in your button click handler:
If nextInd <= 49 Then ' Make sure you are not trying to fill values past the dimensions of the array
states(nextInd, 0) = textbox1.text
states(nextInd, 1) = textbox2.text
nextInd += 1 ' To increment the next index to use by 1
textbox1.text = ""
textbox2.text = ""
End If
And then to display the contents of the array, you need a loop:
' Use a string builder so you can modify the same string object to show it all together in the message box
Dim contents As New StringBuilder("")
For st = 0 To 49
contents.Append(states(st, 0) & ": " & states(st, 1) & Environment.NewLine)
' Or however you want To format it
Next
MessageBox.Show(Me, contents) ' MsgBox is old - use MessageBox instead
I am trying to use this code to remove spaces from a listbox but it is not working
Dim word As String() = {" "}
For i As Integer = 0 To ListBox5.Items.Count - 1
For Each Word As String In word
If ListBox5.Items(i).ToString.Contains(Word) Then
ListBox5.Items(i) = ListBox5.Items(i).ToString.Replace(Word, String.Empty)
End If
Next
Next
any help would be appreciated a lot.
You define a string array with one value and its static, why?
It seems you could do this simply by coding it like this
scan every item and replace " " with string.empty,
don't bother checking if it exists, just run the replace statement on every item
For i As Integer = 0 To ListBox5.Items.Count - 1
ListBox5.Items(i) = ListBox5.Items(i).ToString.Replace(" ", String.Empty)
Next
try this code
For i As Integer = 0 To ListBox5.Items.Count - 1
ListBox5.Items(i) = ListBox5.Items(i).ToString.Replace(" ", Nothing)
Next
fist we have to loop through the listbox items. we declared the items from index 0 to the final item index,ie listbox.items.count-1 . this is stored in a variable i. next all the items ,say from 0 to count-1 is replaced.
istBox5.Items(i).ToString.Replace(" ", Nothing) " " indicates a space and'nothing' indicates null.you can also use regex.replace here by importing system.regularexpressions.
I am trying to perform a SQL Select query based on the user input from a Checked List Box. I was able to find some code, but the solution doesn't seem to be working. On the debug, it keeps crapping out on line 3 and I have no idea why.
Any help would be grateful.
Dim DistrictString As StringBuilder = New StringBuilder()
For h = 0 To Me.District.CheckedItems.Count - 1
If Me.District.CheckedItems(h).Selected Then
DistrictString.Append(Me.District.CheckedItems(h).Value & ",")
End If
Next
With some of the advice, here is the newly edited version of the code, it is now crashing on the Append line.
The new error is 'Public member 'Value' on type 'String' not found'
Dim DistrictW As String
Dim DistrictX As String
Dim DistrictString As StringBuilder = New StringBuilder
For h = 0 To Me.District.CheckedItems.Count - 1
DistrictString.Append(Me.District.CheckedItems(h).Value & ",")
Next
DistrictW = DistrictString.ToString
DistrictX = DistrictW.Substring(0, DistrictString.Length - 1)
If Me.District.CheckedItems.Items(h).Selected Then
DistrictString.Append(Me.District.CheckedItems.Items(h).Value & ",")
End If
Use CheckboxList.Items
Thank you to everyone who helped, this is the solution that I implemented
Learned a lot from this little exercise.
Dim DistrictW As String
Dim DistrictX As String
Dim DistrictString As StringBuilder = New StringBuilder
For h = 0 To Me.District.CheckedItems.Count - 1
DistrictString.Append(Me.District.CheckedItems(h).ToString & ",")
Next
DistrictW = DistrictString.ToString
DistrictX = DistrictW.Substring(0, DistrictString.Length - 1)
Since it appears you are creating a expression like ...xyz in ('a', 'b', 'c', 'd')... the following code might be more appropriate:
For h = 0 To Me.District.CheckedItems.Count - 1
DistrictString += "'" & Me.District.CheckedItems(h).Value & "',"
Next
DistrictString = DistrictString.Substring(0, DistrictString.Length - 1)
There is no point in messing with the .SELECTED property at all. Everything that's checked is 'selected' for your purposes.
Using a SELECT statement I query a database and get back a result in the format: name1,name2,name3
Depending on the database entry this result could have any number of names: name1,name2...name(n)
I would like to use this data to query another database like so:
SELECT Name, SerialNo, Model FROM InstrumentTable where ID=1 and InstName IN name1,name2,name3
In order to do this I need to convert name1,name2,name3 to ('name1','name2','name3')
I have tried splitting the String into an array of Strings
Dim ref1s As String = cmdf1.ExecuteScalar()
Dim fields() As String = Nothing
fields = ref1s.Split(",")
and then concatenating them in an array
For i As Integer = 0 To fields.Count - 1
MsgBox(String.Concat("'", fields(i), "'"))
Next
but I haven't been able to figure out how to do it yet.
Adding the brackets at the start and end of the string shouldn't be a problem just adding the quotes to each name and separating them with a comma is the issue.
Can anyone help me with this?
You got a bit previous
For i As Integer = 0 To fields.Count - 1
fields[i] = String.Concat("'",fields[i],"'")
Next
Then
strValue = fields.Join(',')
user557425,
Something like this might point you in the right direction:
Dim lst As List(Of String)
For i As Integer = 0 to fields.Count - 1
if i = fields.Count - 1 Then
lst.Add(fields(i) & "'")
Else
lst.Add(fields(i) & "','")
End if
Next
Dim sqlSB As StringBuilder
sqlSB.Append("SELECT * FROM TABLE WHERE BLAH IN(")
For each s As String in lst
sqlSB.Append(s)
Next
'use the stringbuilder as command text in a SqlCommand...
I'm making an application that will change position of two characters in Word.
Imports System.IO
Module Module1
Sub Main()
Dim str As String = File.ReadAllText("File.txt")
Dim str2 As String() = Split(str, " ")
For i As Integer = 0 To str2.Length - 1
Dim arr As Char() = CType(str2(i), Char())
For ia As Integer = 0 To arr.Length() - 1 Step 2
Dim pa As String
pa = arr(ia + 1)
arr(ia + 1) = arr(ia)
arr(ia) = pa
Next ia
For ib As Integer = 0 To arr.Length - 1
Console.Write(arr(ib))
File.WriteAllText("File2.txt", arr(ib))
Next ib
File.WriteAllText("File2.txt", " ")
Console.Write(" ")
Next i
Console.Read()
End Sub
End Module
For example:
Input: ab
Output: ba
Input: asdasd asdasd
Output: saadds saadds
Program works good, it is mixing characters good, but it doesn't write text to the file. It will write text in console, but not in file.
Note: Program is working only with words that are divisible by 2, but it's not a problem.
Also, it does not return any error message.
Your code is overwriting the file that you have already written with a single space (" ") each time round.
You should only open the file once, and append to it using a stream writer:
Using output = File.CreateText("file2.txt")
' Put the for loop here.
End Using
There are some other things wrong with your code. Firstly, use For Each instead of For, this makes your code much more simple and readable. Secondly, try to avoid For loops altogether where possible. For instance, instead of iterating over the characters to output them one at a time, just create a new string from the char array, and write that:
Dim shuffledWord As New String(arr)
output.Write(shuffledWord)
Some of your types are plain wrong, i.e. you are using String in places instead of Char. You should always use Option Strict On. Then the compiler will not tolerate such code.
You should also prefer to use framework methods over VB-specific methods. This makes it easier to understand for C# programmers, and also makes it easier to translate and change (that is, use the Split method of strings instead of a free function, use ToCharArray instead of a cast to Char() …).
Finally, use meaningful variable names. str, str2 and arr are particularly cryptic because they don’t tell the reader of the code anything of interest about the variables.
Sub Main()
Dim text As String = File.ReadAllText("File.txt")
Dim words As String() = str.Split(" "c)
Using output = File.CreateText("file2.txt")
For Each word In words
dim wordChars = word.ToCharArray()
For i As Integer = 0 To wordChars.Length - 1 Step 2
Dim tmp As Char = wordChars(i + 1)
wordChars(i + 1) = wordChars(i)
arr(i) = tmp
Next
Dim shuffledWord As New String(wordChars)
output.Write(shuffledWord + " ")
Console.Write(huffledWord + " ")
Next
End Using
Console.Read()
End Sub