I am trying to run an event which will search through the different files in a given directory. The goal is to have it search for all files that begin with 'SP_', which are .sql files containing Stored Procedures. I would then like to add the full text of these Procedures to an array to be used later. This is causing an error when run, which I believe is because 'FullProcedureArray()', the string array I am trying to load does not have defined boundaries. When I declare it as 'FullProcedureArray(7)', or with some other value, it appears to run fine. But I don't want to have to hard-code a boundary for 'FullProcedureArray'; I would rather let it be defined by whatever the number of files in the folder is.
My question: Is there a way to declare 'FullProcedureArray' without having to give it an absolute value? I may just be missing something painfully obvious, but I haven't worked with this type of array much in the past. Thanks in advance for your help.
Dim AppDataLocation As String = "C:\Files\TestFiles\"
Dim ProcedureArray As String()
Dim ProcedureText As String
Dim FullProcedureArray() As String
Dim sourceDirectoryInfo As New System.IO.DirectoryInfo(AppDataLocation)
Dim fileSystemInfo As System.IO.FileSystemInfo
Dim i As Integer = 0
For Each fileSystemInfo In sourceDirectoryInfo.GetFileSystemInfos
If (fileSystemInfo.Name.Contains("SP_")) Then
ProcedureArray = System.IO.File.ReadAllLines(AppDataLocation & fileSystemInfo.Name)
ProcedureText = Join(ProcedureArray, "")
FullProcedureArray.SetValue(ProcedureText, i)
i = (i + 1)
End If
Next
An array by definition has a fixed upper bound. If you don't want a fixed upper bound, don't use an array. Use, for example, a List(Of String) instead:
Dim AppDataLocation As String = "C:\Files\TestFiles\"
Dim ProcedureList As New List(Of String)
Dim sourceDirectoryInfo As New System.IO.DirectoryInfo(AppDataLocation)
For Each fileSystemInfo As System.IO.FileSystemInfo In sourceDirectoryInfo.GetFileSystemInfos
If (fileSystemInfo.Name.Contains("SP_")) Then
Dim ProcedureText As String = _
System.IO.File.ReadAllText(AppDataLocation & fileSystemInfo.Name)
ProcedureList.Add(ProcedureText)
End If
Next
If, for some reason, you still need the result as an array afterwards, simply convert the list to an array:
Dim myArray() As String = ProcedureList.ToArray()
If you don't want to give a size to your array or want to change at runtime, you can use "Redim Preserve"
http://msdn.microsoft.com/en-us/library/w8k3cys2%28v=vs.71%29.aspx
Related
I had built a project that read data from a report and it used to work fine but now for some reason the report puts every thing in to strings. So I want to modify my stream reader to remove or ignore the quotes as it reads the lines.
This is a snipet of the part that reads the lines.
Dim RawEntList As New List(Of Array)()
Dim newline() As String
Dim CurrentAccountName As String
Dim CurrentAccount As Account
Dim AccountNameExsists As Boolean
Dim NewAccount As Account
Dim NewEntry As Entrey
Dim WrongFileErrorTrigger As String
ListOfLoadedAccountNames.Clear()
'opens the file
Try
Dim sr As New IO.StreamReader(File1Loc)
Console.WriteLine("Loading full report please waite")
MsgBox("Loading full report may take a while.")
'While we have not finished reading the file
While (Not sr.EndOfStream)
'spliting eatch line up into an array
newline = sr.ReadLine.Split(","c)
'storring eatch array into a list
RawEntList.Add(newline)
End While
And then of course I iterate through the list to pull out information to populate objects like this:
For Each Entr In RawEntList
CurrentAccountName = Entr(36)
AccountNameExsists = False
For Each AccountName In ListOfLoadedAccountNames
If CurrentAccountName = AccountName Then
AccountNameExsists = True
End If
Next
You could just do
StringName.Replace(ControlChars.Quote, "")
or
StringName.Replace(Chr(34), "")
OR
streamReader.readline.split().Replace(Chr(34), "")
How about doing the replace before the split, after the readline? That should save iteration multiplication, or better yet (if possible), do a replace on the entire file (if the data is formatted in the way it can be done & you have enough memory) using the ReadAllText method of the File object, do your replace, then read the lines from memory to build your array (super fast!).
File.ReadAllText(path)
I'm using Visual studio to build a small utility.
I'm importing variables from a text file (this makes my program expandable in the future).
I'm running into a road block trying to split the variables into usable parts.
The text file is set up as such:
Game1:flshflhdlsfsdsfs
Game2:ugdjgndrgbdvdnjd
Game3:gnnereknengievke
And the code I've gathered from searching around trying to understand how I could do this is (It's gone through multiple rewrites but I feel this is probably the closest I've gotten):
Dim value As String = File.ReadAllText("Games.txt")
Dim cut_at As String = ":"
Dim x As Integer = InStr(value, cut_at)
Dim string_before As String = value.Substring(0, x - 2)
Dim string_after As String = value.Substring(x + cut_at.Length - 1)
Games_drp.Items.AddRange(string_before)
When I run a test like this, I get an error that String_before cannot be converted to an object. I tried switching "Dim string_before As String = value.Substring(0, x - 2)" to Dim string_before As Object = value.Substring(0, x - 2), but the dropdown that's supposed to be populated by at least one of the entries before the : has absolutely nothing in it.
Being pretty new at VB and feeling like I've exhausted pretty much every way I could think of searching in google and trying to piece together various bits of information, I figure I'd try asking my own direct question:
How would I go about reading all the lines from a text file, then splitting before the : to fill a combobox, and using a label to display the string after the : matching which ever entry is selected in the dropdown.
Thanks in advance for any help.
EDIT with full code:
Imports System.IO
Public Class Saves_frm
Private Sub Saves_frm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim value As String = File.ReadAllText("Games.txt")
Dim cut_at As String = ":"
Dim x As Integer = InStr(value, cut_at)
Dim string_before As String = value.Substring(0, x - 2)
Dim string_after As String = value.Substring(x + cut_at.Length - 1)
Games_drp.Items.AddRange(string_before)
End Sub
End Class
When run as is, I get an error that 'string_before' can't be converted from a string to an object, but when I make the following change from:
Dim string_before As String = value.Substring(0, x - 2)
to:
Dim string_before As Object = value.Substring(0, x - 2)
The error goes away, but the dropdown remains blank.
It's easier to use File.ReadAllLines, as it returns an array with all the file's lines. Then, you can loop through the lines, splitting each line and adding the result to the ListBox. This should be an example, but feel free to correct any mistakes I made, as I wrote it on my phone and it's been a long time since I used VB.
Dim lines() As String = File.ReadAllLines("file.txt")
For Each line As String In lines
Dim split() As String = line.Split(":"c)
gDic.Add(split(0), split(1))
Next
EDIT: Then, you most certainly want a dictionary that contains the name and the data, check the updated code.
Then, add the names by looping through gDic.Keys. When a name is selected, access its value with gDic("key").
Needed code is something like this:
Dim myArray(0) As String
Dim ay As String = "ay"
myArr & ay(0) = "asd"
I've tried but did not worked
Dim classlist1(0) As String
Dim classlist2(0) As String
Dim classlist3(0) As String
Dim classlist4(0) As String
Dim count As Integer = 0
For _year As Integer = 1 To 4
("classlist" & _year)(count) = "hi"
count += 1
Next
Any time you see something like this:
Dim classlist1(0) As String
Dim classlist2(0) As String
Dim classlist3(0) As String
' etc.
It's an indication that you're using the wrong data structure. Instead of trying to dynamically build variable names (which isn't really possible in a static language, at least not without some really ugly reflection code with a high potential for runtime errors), just use a collection.
For example, if you want a collection of strings:
Dim classList As New List(Of String)()
And if you want a collection of collections of strings:
Dim classLists As New List(Of List(Of String))()
Then you can reference the nested lists within the parent list. So to add your first "year" of classes:
classLists.Add(new List(Of String))
And add a class to that year:
classLists(0).Add("some value")
As you can see, it starts to get a little difficult to keep track of the data structures. This is where creating custom types and structures becomes very useful. For example, rather than representing a "year" as a list of strings, create an actual Year class. That class can internally hold a list of strings, and other logic/data.
Try Dictionary<TKey, TValue> Class From MSDN.
Dim classLists As New Dictionary(Of String, String)()
'Add items with keys
For _year As Integer = 1 To 4
classLists.Add(String.Format("classlist{0}",_year), "hi")
Next
And you can get value by key later
Dim key As String = "classlist2"
Dim value As String = classLists(key)
I am using Visual Studio.net, Visual Basic and I have a question.
If I have a string that has many lines in it, what is the best way to get the contents of a certain line?
E.g If the string is as follows:
Public Property TestProperty1 As String
Get
Return _Name
End Get
Set(value As String)
_Name = value
End Set
End Property
What is the best way to get the contents of line 2 ("Get")?
The simplest is to use ElementAtOrdefault since you don't need to check if the collection has so many items. It would return Nothing then:
Dim lines = text.Split({Environment.NewLine}, StringSplitOptions.None)
Dim secondLine = lines.ElementAtOrDefault(1) ' returns Nothing when there are less than two lines
Note that an index is zero-based, hence i have used ElementAtOrDefault(1) to get the second line.
This is the non-linq approach:
Dim secondLine = If(lines.Length >= 2, lines(1), Nothing) ' returns Nothing when there are less than two lines
That depends on what you mean by "best".
The easiest, but least efficient, is to split the string into lines and get one of them:
Dim second As String = text.Split(Environment.NewLine)(1)
The most efficient would be to locate the line breaks in the string and get the line using Substring, but takes a bit more code:
Dim breakLen As Integer = Environment.Newline.Length;
Dim firstBreak As Integer = text.IndexOf(Environment.Newline);
Dim secondBreak As Integer = text.IndexOf(Environment.NewLine, firstBreak + breakLen)
Dim second As String = text.Substring(firstBreak + breakLen, secondBreak - firstBreak - breakLen)
To get any line, and not just the second, you need even more code to loop through the lines until you get to the right one.
Been following the threads for sometime as a novice (more of a newbie) but am now starting to do more.
I can read how to open a text file but am having trouble understanding the .replace functionality (I get the syntax just can't get it to work).
Scenario:
Inputfile name = test_in.txt
replace {inputfile} with c:\temp\test1.txt
I'm using test.txt as a template for a scripting tool and need to replace various values within to a new file called test_2.txt.
I've got variables defining the input and output files without a problem, I just can't catch the syntax for opening the new file and replacing.
You really have not given us that much to go on. But a common mistake in using String.Replace is that it makes a copy of the source which needs to be saved to another variable or else it will go into the bit bucket. So in your case, something like this should work.
Dim Buffer As String 'buffer
Dim inputFile As String = "C:\temp\test.txt" 'template file
Dim outputFile As String = "C:\temp\test_2.txt" 'output file
Using tr As TextReader = File.OpenText(inputFile)
Buffer = tr.ReadToEnd
End Using
Buffer = Buffer.Replace("templateString", "Hello World")
File.WriteAllText(outputFile, Buffer)
Try something like this:
Dim sValuesToReplace() As String = New String() {"Value1", "Value2", "Value3"}
Dim sText As String = IO.File.ReadAllText(inputFilePath)
For Each elem As String In sValuesToReplace
sText = sText.Replace(elem, sNewValue)
Next
IO.File.WriteAllText(sOutputFilePath, sText)
It depends if you want to replace all values with only one value, or with different values for each. If you need different values you can use a Dictionary:
Dim sValuesToReplace As New Dictionary(Of String, String)()
sValuesToReplace.Add("oldValue1", "newValue1")
sValuesToReplace.Add("oldValue2", "newValue2")
'etc
And then loop throgh it with:
For Each oldElem As String In sValuesToReplace.Keys
sText = sText.Replace(oldElem, sValuesToReplace(oldElem))
Next