How do you use the connection string on a local database in a way that would allow you to transfer the project folder from one computer to another, without having to modify the connection string?
Not like this
connection_String As String = "Data Source=C:\Users\Kyle\Desktop\CSCI_388_Group_Project\CSCI_388_Group_Project\CSCI_388_Group_Project\CSCI_388_Group_Project_Database.sdf"
More like this
connection_String As String = "Data Source=|DataDirectory|\CSCI_388_Group_Project_Database.sdf"
If I try to enter the second example into the connection field under the database properties I get an illegal character error.
The Environment class contains most of the paths you'll need.
You can call Environment.GetFolderPath to get a special directory. For example, to get the My Documents directory, call Environment.GetFolderPath(Environment.SpecialFolder.Personal).
You can browse all of the special folders here:
http://msdn.microsoft.com/en-us/library/system.environment.specialfolder.aspx
In your example specifically, you'd use the following:
connection_String As String = _
"Data Source=" &
Path.Combine(
Environment.GetFolderPath(Environment.SpecialFolder.Desktop),
"CSCI_388_Group_Project_Database.sdf" )
Alternative:
Is it possible to just ask the user? If it's on their desktop, they might move it.
If you decide to keep the sdf file in the same folder in which your exe would reside, then you can do like this.
Dim ExeFolder As String = AppDomain.CurrentDomain.BaseDirectory
Dim connection_String As String = "Data Source=" & ExeFolder & "CSCI_388_Group_Project_Database.sdf"
Hope it helps !
One simple way is to use an environment variable to specify your path to the folder.
Then in your VB program using the Environ function to get the environment variable settings and use string manipulation to build your connect string.
You will need to have a default in case the environment variable is not set.
However when you launch your application, you can do it within a script that will set the environment variable.
A second method is to specify the path name on the application command line so that when the application is launched, it will specify the path using the command line.
A third method is to have a Windows registry key that you use. Then, similar to the environment variable, you query the Windows Registry for the folder path, then build your connect string from that.
With this third method you can have your application installer insert the Registry key.
A fourth method is to have an .ini file that contains an entry for the folder path.
Related
Is there a way of grabbing the location of the My.Settings user.config location? So for example I want to be able in VB to grab the path of the user.cofing file path to a string
The reason I ask is that I have an application where the user.config file is backed up and then restored, the issue is that with the my.settings folder structure it uses a unique hash with the folder name meaning that I cannot write into the code a static folder path, instead I need to be able to grab the location of the user.config OR be able to get the folder name of the application AppData.
Any ideas?
To put this in perspective, currently I'm using something like this:
Dim filePath As String
filePath = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData) & "\My_App\My_App.exe_Url_<the_hash_that_changes_causing_issues>\1.0.0.0\user.config"
Because of the hash change this will not always work
Try executing this code:
Dim mainConfig = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)
Dim userConfig = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.PerUserRoaming)
Dim userLocalConfig = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.PerUserRoamingAndLocal)
Console.WriteLine(mainConfig.FilePath)
Console.WriteLine(userConfig.FilePath)
Console.WriteLine(userLocalConfig.FilePath)
You'll need to reference System.Configuration.dll and import System.Configuration.
I'm working with vb.net 2008 as well. But I have a question.How to remove a file path like this C:\users\myDocu\debug\Dbase.accdb and I only want is the file name Dbase.accdb. Because I want to transfer my files in another computer but the problem is the file path. I always need to change the entire location in my codes to run without debug.
To get the filename without the path, you can use Path.GetFileName.
But if you want a painless way to find a place to store your database, consider putting it into the application data folder (AppData). You can get this folder with Environment.GetFolderPath and Environment.SpecialFolder.ApplicationData, using it like this:
Dim pathToDb = Path.Combine(
Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
"Dbase.accdb")
if you want to use the file locally. If you want to share the file between different instances of your application in a network, put the path e.g. in a config file like App.Config.
Try this:
Dim FullFilePath As String
Dim FileName As String
FullFilePath = "C:\users\myDocu\debug\Dbase.accdb"
FileName = Mid(FullFilePath,InStrRev(FullFilePath,"\") + 1)
I made a desktop application in vb.net. I give the reference path of connection string through the .udl. The problem is when I place the folder in another location the path string does not change and hence results in an error. Kindly suggest. Connection details are as follows
_connStr = System.IO.File.ReadAllText("C:\Users\avt\Desktop\New folder\a.udl")
con = New OleDbConnection(_connStr)
First of all, why are you using Text file to save your connection String ?
Go to Project Properties -> Settings and create a ConnectionString setting to save your connection string. That'll solve your problem. Using a Text file for ConnectionString is not a valid way.
My Visual Basic project uses this connecton string:
Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Users\Admin\Desktop\IzolacCold V2\IzolacCold V2\izolac_cold_dbv2.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True
When I debug it, and go to debug folder, or when I "Release" it then problem occurs. If I run exe file program works normally but it save's data in database defined in connection string and not in database that is created in DEBUG folder (or RELESE folder).
How to properly connect to my databes. How to build proper connection string ?
You should use the DataDirectory substitution string.
For example you could write your connectionstring as
Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\izolac_cold_dbv2.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True
In your code then you could control the exact location of the DataDirectory executing this code, BEFORE any attempt to open a connection.
Dim commonDataFolder = Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData)
Dim myAppDataFolder = Path.Combine(commonDataFolder, "MyAppName")
if Not Directory.Exists(myAppDataFolder) Directory.CreateDirectory(myAppDataFolder)
AppDomain.CurrentDomain.SetData("DataDirectory", myAppDataFolder)
(This example use the C:\programdata\myAppName folder because it is the most appropriate location for read/write data files needed by your application
Your deployment procedure should take care to create the above folder and place the database file in this location.
I have a class library which reads the XML file.
I am using VS 2012 and VB.NET language.
I am getting confused about how to read the file which is in folder of a application itself.
Right now I have given the path as
Dim reader As XmlTextReader = New XmlTextReader("C:\mailpara.xml")
but its hard-coded , but I want to make a folder in app. and want to read from that
folder itself.
I want to know how to read the file from the folder of a application.
How to read the file after installation on client's machine and how to add the file while making the set up ?
Use something like;
Dim directory as String = My.Application.Info.DirectoryPath
Dim reader As XmlTextReader = New XmlTextReader(directory & "\MyFolderName\mailpara.xml")
You can use Application.StartupPath property to retrieve the startup path of the application.
Dim reader As XmlTextReader = New XmlTextReader(Application.StartupPath & "mailpara.xml")
You might want to add a check to ensure that the path ends with a \ (I think it may or may not be present depending on whether the path is a root folder or not).