Using System.Configuration.ConfigurationManager Example (VB.NET)
Article
Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text
Imports System.Configuration
Imports System.Collections
Imports System.Collections.Specialized
Imports System.Diagnostics
' The following example shows how to use the ConfigurationManager
' class in a console application.
'
' IMPORTANT: To compile this example, you must add to the project
' a reference to the System.Configuration assembly.
'
Namespace Samples.Aspnet
#Region "Auxiliary Classes"
' Define a custom configuration element to be
' contained by the ConsoleSection. This element
' stores background and foreground colors that
' the application applies to the console window.
Public Class ConsoleConfigElement
Inherits ConfigurationElement
' Create the element.
Public Sub New()
End Sub
' Create the element.
Public Sub New(ByVal fColor As ConsoleColor, _
ByVal bColor As ConsoleColor)
ForegroundColor = fColor
BackgroundColor = bColor
End Sub
' Get or set the console background color.
<ConfigurationProperty("background", _
DefaultValue:=ConsoleColor.Black, IsRequired:=False)> _
Public Property BackgroundColor() As ConsoleColor
Get
Return DirectCast(Me("background"), ConsoleColor)
End Get
Set(ByVal value As ConsoleColor)
Me("background") = value
End Set
End Property
' Get or set the console foreground color.
<ConfigurationProperty("foreground", _
DefaultValue:=ConsoleColor.White, IsRequired:=False)> _
Public Property ForegroundColor() As ConsoleColor
Get
Return DirectCast(Me("foreground"), _
ConsoleColor)
End Get
Set(ByVal value As ConsoleColor)
Me("foreground") = value
End Set
End Property
End Class
' Define a custom section that is used by the application
' to create custom configuration sections at the specified
' level in the configuration hierarchy.
' This enables the the user that has the proper access
' rights, to make changes to the configuration files.
Public Class ConsoleSection
Inherits ConfigurationSection
' Create a configuration section.
Public Sub New()
End Sub
' Set or get the ConsoleElement.
<ConfigurationProperty("consoleElement")> _
Public Property ConsoleElement() _
As ConsoleConfigElement
Get
Return (DirectCast(Me("consoleElement"), _
ConsoleConfigElement))
End Get
Set(ByVal value As ConsoleConfigElement)
Me("consoleElement") = value
End Set
End Property
End Class
#End Region
#Region "ConfigurationManager Interaction Class"
' The following code uses the ConfigurationManager class to
' perform the following tasks:
' 1) Get the application roaming configuration file.
' 2) Get the application configuration file.
' 3) Access a specified configuration file through mapping.
' 4) Access the machine configuration file through mapping.
' 5) Read a specified configuration section.
' 6) Read the connectionStrings section.
' 7) Read or write the appSettings section.
Public Class UsingConfigurationManager
' Get the roaming configuration file associated
' with the application.
' Note.This function uses the OpenExeConfiguration(
' ConfigurationUserLevel userLevel) method to
' get the configuration file.
Public Shared Sub GetRoamingConfiguration()
' Define the custom section to add to the
' configuration file.
Dim sectionName As String = "consoleSection"
Dim cSection As ConsoleSection = Nothing
' Get the roaming configuration
' that applies to the current user.
Dim roamingConfig As Configuration = _
ConfigurationManager.OpenExeConfiguration( _
ConfigurationUserLevel.PerUserRoaming)
' Map the roaming configuration file. This
' enables the application to access
' the configuration file using the
' System.Configuration.Configuration class
Dim configFileMap As New ExeConfigurationFileMap()
configFileMap.ExeConfigFilename = roamingConfig.FilePath
' Get the mapped configuration file.
Dim config As Configuration = _
ConfigurationManager.OpenMappedExeConfiguration( _
configFileMap, ConfigurationUserLevel.None)
Try
cSection = DirectCast(config.GetSection(sectionName), _
ConsoleSection)
If cSection Is Nothing Then
' Create a custom configuration section.
cSection = New ConsoleSection()
' Define where in the configuration file
' hierarchy the associated
' configuration section can be declared.
cSection.SectionInformation.AllowExeDefinition = _
ConfigurationAllowExeDefinition.MachineToLocalUser
' Allow the configuration section to be
' overridden by other configuration files.
cSection.SectionInformation.AllowOverride = True
' Force the section to be saved.
cSection.SectionInformation.ForceSave = True
' Store console settings for roaming users.
cSection.ConsoleElement.BackgroundColor = _
ConsoleColor.Blue
cSection.ConsoleElement.ForegroundColor = _
ConsoleColor.Yellow
' Add configuration information to
' the configuration file.
config.Sections.Add(sectionName, cSection)
config.Save(ConfigurationSaveMode.Modified)
' Force a reload of the changed section. This
' makes the new values available for reading.
ConfigurationManager.RefreshSection(sectionName)
End If
Catch e As ConfigurationErrorsException
Console.WriteLine("[Exception error: {0}]", _
e.ToString())
End Try
' Set console properties using values
' stored in the configuration file.
Console.BackgroundColor = _
cSection.ConsoleElement.BackgroundColor
Console.ForegroundColor = _
cSection.ConsoleElement.ForegroundColor
' Apply the changes.
Console.Clear()
' Display feedback.
Console.WriteLine()
Console.WriteLine("Performed the following tasks:")
Console.WriteLine("Created roaming configuration file {0}", config.FilePath)
Console.WriteLine("Created custom ConsoleSection.")
Console.WriteLine( _
"Stored background (blue) and foreground (yellow) colors.")
Console.WriteLine( _
"Added the section to the configuration file.")
Console.WriteLine( _
"Read stored colors from the configuration file.")
Console.WriteLine( _
"Applied the colors to the console window.")
Console.WriteLine()
End Sub
' Get the application configuration file.
' Note. This function uses the
' OpenExeConfiguration(string)method
' to get the application configuration file.
Public Shared Sub GetAppConfiguration()
' Get the application path needed to obtain
' the application configuration file.
Dim applicationName As String = _
Environment.GetCommandLineArgs()(0) + ".exe"
Dim exePath As String = _
System.IO.Path.Combine(Environment.CurrentDirectory, _
applicationName)
' Get the configuration file. The file name has
' this format appname.exe.config.
Dim config As System.Configuration.Configuration = _
ConfigurationManager.OpenExeConfiguration(exePath)
Try
' Create a custom configuration section
' having the same name used in the
' roaming configuration file.
' This is possible because the configuration
' section can be overridden by other
' configuration files.
Dim sectionName As String = "consoleSection"
Dim customSection As New ConsoleSection()
If config.Sections(sectionName) Is Nothing Then
' Store console settings.
customSection.ConsoleElement.BackgroundColor = _
ConsoleColor.Black
customSection.ConsoleElement.ForegroundColor = _
ConsoleColor.White
' Add configuration information to the
' configuration file.
config.Sections.Add(sectionName, customSection)
config.Save(ConfigurationSaveMode.Modified)
' Force a reload of the changed section.
' This makes the new values available for reading.
ConfigurationManager.RefreshSection(sectionName)
End If
' Set console properties using values
' stored in the configuration file.
customSection = DirectCast(config.GetSection(sectionName), _
ConsoleSection)
Console.BackgroundColor = _
customSection.ConsoleElement.BackgroundColor
Console.ForegroundColor = _
customSection.ConsoleElement.ForegroundColor
' Apply the changes.
Console.Clear()
Catch e As ConfigurationErrorsException
Console.WriteLine("[Error exception: {0}]", e.ToString())
End Try
' Display feedback.
Console.WriteLine()
Console.WriteLine("Performed the following tasks:")
Console.WriteLine( _
"Created the application configuration file {0}", _
config.FilePath)
Console.WriteLine("Created custom ConsoleSection.")
Console.WriteLine( _
"Stored background (black) and foreground (white) colors.")
Console.WriteLine( _
"Added the section to the configuration file.")
Console.WriteLine( _
"Read stored colors from the configuration file.")
Console.WriteLine( _
"Applied the colors to the console window.")
Console.WriteLine()
End Sub
' Get the AppSettings section.
' This function uses the AppSettings property
' to read the appSettings configuration
' section.
Public Shared Sub ReadAppSettings()
Try
' Get the AppSettings section.
Dim appSettings As NameValueCollection = _
ConfigurationManager.AppSettings
' Get the AppSettings section elements.
Console.WriteLine()
Console.WriteLine("Performed the following tasks:")
Console.WriteLine("Read application settings:")
Console.WriteLine()
If appSettings.Count = 0 Then
Console.WriteLine( _
"[ReadAppSettings: {0}]", _
"AppSettings is empty Use GetSection command first.")
End If
Dim i As Integer = 0
While i < appSettings.Count
Console.WriteLine("#{0} Key: {1} Value: {2}", i, _
appSettings.GetKey(i), appSettings(i))
System.Math.Max( _
System.Threading.Interlocked.Increment(i), i - 1)
End While
Catch e As ConfigurationErrorsException
Console.WriteLine("[ReadAppSettings: {0}]", _
e.ToString())
End Try
End Sub
' Get the ConnectionStrings section.
' This function uses the ConnectionStrings
' property to read the connectionStrings
' configuration section.
Public Shared Sub ReadConnectionStrings()
' Get the ConnectionStrings collection.
Dim connections _
As ConnectionStringSettingsCollection = _
ConfigurationManager.ConnectionStrings
If connections.Count <> 0 Then
Console.WriteLine()
Console.WriteLine("Performed the following tasks:")
Console.WriteLine("Read connection strings:")
Console.WriteLine()
' Get the collection elements.
For Each connection _
As ConnectionStringSettings In connections
Dim name As String = connection.Name
Dim provider As String = connection.ProviderName
Dim connectionString As String = _
connection.ConnectionString
Console.WriteLine("Name: {0}", _
name)
Console.WriteLine("Connection string: {0}", _
connectionString)
Console.WriteLine("Provider: {0}", _
provider)
Next
Else
Console.WriteLine()
Console.WriteLine( _
"No connection string is defined.")
Console.WriteLine()
End If
End Sub
' Create the AppSettings section.
' The function uses the GetSection(string)method
' to access the configuration section.
' It also adds a new element to the section
' collection.
Public Shared Sub CreateAppSettings()
' Get the application configuration file.
Dim config As System.Configuration.Configuration = _
ConfigurationManager.OpenExeConfiguration( _
ConfigurationUserLevel.None)
Dim sectionName As String = "appSettings"
' Add an entry to appSettings.
Dim appStgCnt As Integer = _
ConfigurationManager.AppSettings.Count
Dim newKey As String = "NewKey" + appStgCnt.ToString()
Dim newValue As String = _
DateTime.Now.ToLongDateString() + " " + _
DateTime.Now.ToLongTimeString()
config.AppSettings.Settings.Add(newKey, newValue)
' Save the configuration file.
config.Save(ConfigurationSaveMode.Modified)
' Force a reload of the changed section. This
' makes the new values available for reading.
ConfigurationManager.RefreshSection(sectionName)
' Get the AppSettings section.
Dim appSettingSection As AppSettingsSection = _
DirectCast(config.GetSection(sectionName), _
AppSettingsSection)
' Display raw xml.
Console.WriteLine()
Console.WriteLine("Performed the following tasks:")
Console.WriteLine("Created AppSettings section.")
Console.WriteLine("Added new element to the section.")
Console.WriteLine("Read the following settings:")
Console.WriteLine()
' Get the AppSettings XML.
Console.WriteLine( _
appSettingSection.SectionInformation.GetRawXml())
End Sub
' Access a configuration file using mapping.
' This function uses the OpenMappedExeConfiguration
' method to access the roaming and the application
' configuration files.
' It then uses the the custom ConsoleSection from
' each file to console window colors.
Public Shared Sub MapExeConfiguration()
' Cotains the selected configuration.
Dim config As System.Configuration.Configuration
' Get the roaming configuration file.
Dim roamingConfig As Configuration = _
ConfigurationManager.OpenExeConfiguration( _
ConfigurationUserLevel.PerUserRoaming)
' Get the application configuration file.
Dim appConfig As Configuration = _
ConfigurationManager.OpenExeConfiguration( _
ConfigurationUserLevel.None)
' To map the selected configuration file.
Dim configFileMap As New ExeConfigurationFileMap()
' Map roaming configuration. This allows
' access to the roaming configuration file.
configFileMap.ExeConfigFilename = roamingConfig.FilePath
' Get the mapped configuration file
config = _
ConfigurationManager.OpenMappedExeConfiguration( _
configFileMap, ConfigurationUserLevel.None)
Dim sectionName As String = "consoleSection"
Dim customSection As ConsoleSection = _
DirectCast(config.GetSection(sectionName), _
ConsoleSection)
' Set console properties using the
' configuration values contained in the
' mapped configuration file.
Console.BackgroundColor = _
customSection.ConsoleElement.BackgroundColor
Console.ForegroundColor = _
customSection.ConsoleElement.ForegroundColor
Console.Clear()
Console.WriteLine()
Console.WriteLine("Performed following tasks:")
Console.WriteLine( _
"Mapped roaming configuration file: {0}", config.FilePath)
Console.WriteLine( _
"Set console colors from stored configuration values.")
Console.WriteLine()
Console.Write( _
"Press Enter to switch to default colors.....")
Console.ReadLine()
' Map roaming configuration. This allows
' access to the application configuration file.
configFileMap.ExeConfigFilename = appConfig.FilePath
' Get the mapped configuration file
config = _
ConfigurationManager.OpenMappedExeConfiguration( _
configFileMap, ConfigurationUserLevel.None)
customSection = _
DirectCast(config.GetSection(sectionName), _
ConsoleSection)
If customSection Is Nothing Then
customSection = New ConsoleSection()
' Store console settings.
customSection.ConsoleElement.BackgroundColor = _
ConsoleColor.Black
customSection.ConsoleElement.ForegroundColor = _
ConsoleColor.White
' Add configuration information to the
' configuration file.
config.Sections.Add(sectionName, customSection)
config.Save(ConfigurationSaveMode.Modified)
' Force a reload of the changed section.
' This makes the new values available for reading.
ConfigurationManager.RefreshSection(sectionName)
End If
' Set console properties using the
' configuration values contained in the
' mapped configuration file.
Console.BackgroundColor = _
customSection.ConsoleElement.BackgroundColor
Console.ForegroundColor = _
customSection.ConsoleElement.ForegroundColor
Console.Clear()
Console.WriteLine( _
"Mapped application configuration file: {0}", _
config.FilePath)
Console.WriteLine( _
"Set console colors from stored configuration values.")
Console.WriteLine()
End Sub
' Access the machine configuration file using mapping.
' The function uses the OpenMappedMachineConfiguration
' method to access the machine configuration.
Public Shared Sub MapMachineConfiguration()
' Get the machine.config3 file.
Dim machineConfig As Configuration = _
ConfigurationManager.OpenMachineConfiguration()
' Get the machine.config file path.
Dim configFile _
As New ConfigurationFileMap(machineConfig.FilePath)
' Map the application configuration file to the machine
' configuration file.
Dim config As Configuration = _
ConfigurationManager.OpenMappedMachineConfiguration( _
configFile)
' Get the AppSettings section.
Dim appSettingSection As AppSettingsSection = _
DirectCast(config.GetSection("appSettings"), _
AppSettingsSection)
appSettingSection.SectionInformation.AllowExeDefinition = _
ConfigurationAllowExeDefinition.MachineToRoamingUser
' Display the configuration file sections.
Dim sections As ConfigurationSectionCollection = _
config.Sections
Console.WriteLine()
Console.WriteLine( _
"Using OpenMappedMachineConfiguration.")
Console.WriteLine( _
"Sections in machine.config:")
' Get the sections in the machine.config.
For Each section As ConfigurationSection In sections
Dim name As String = section.SectionInformation.Name
Console.WriteLine("Name: {0}", name)
Next
End Sub
End Class
#End Region
#Region "User Interaction Class"
' Obtain user's input and provide feedback.
' This class contains the application Main() function.
' It calls the ConfigurationManager methods based
' on the user's selection.
Class ApplicationMain
' Display user's menu.
Public Shared Sub DisplayUserMenu()
Dim applicationName As String = _
Environment.GetCommandLineArgs()(0)
If Not applicationName.Contains(".exe") Then
applicationName = _
[String].Concat(applicationName, ".exe")
End If
Dim buffer As New StringBuilder()
buffer.AppendLine()
buffer.AppendLine("Application: " + applicationName)
buffer.AppendLine("Please, make your selection.")
buffer.AppendLine("Q,q -- Exit the application.")
buffer.Append("1 -- Set console window colors")
buffer.AppendLine(" to blue and yellow")
buffer.AppendLine(" from the roaming configuration.")
buffer.AppendLine("2 -- Ceate appSettings section.")
buffer.AppendLine("3 -- Read appSettings section.")
buffer.AppendLine(" Values merged from application config.")
buffer.Append("4 -- Set console window colors")
buffer.AppendLine(" to black and white")
buffer.AppendLine(" from the application configuration.")
buffer.AppendLine("5 -- Read connectionStrings section.")
buffer.AppendLine(" Values merged from machine.config.")
buffer.AppendLine("6 -- Get specified configuration file.")
buffer.Append(" Set console window colors")
buffer.AppendLine(" from configured values.")
buffer.AppendLine("7 -- Get machine.config file.")
buffer.AppendLine()
Console.Write(buffer.ToString())
End Sub
' Obtain user's input and provide
' feedback.
Shared Sub Main(ByVal args As String())
' Define user selection string.
Dim selection As String = ""
' Get the name of the application.
Dim appName As String = _
Environment.GetCommandLineArgs()(0)
While selection.ToLower() <> "q"
' Process user's input.
Select Case selection
Case "1"
' Show how to use OpenExeConfiguration
' using the configuration user level.
UsingConfigurationManager.GetRoamingConfiguration()
Exit Select
Case "2"
' Show how to use GetSection.
UsingConfigurationManager.CreateAppSettings()
Exit Select
Case "3"
' Show how to use AppSettings.
UsingConfigurationManager.ReadAppSettings()
Exit Select
Case "4"
' Show how to use OpenExeConfiguration
' using the configuration file path.
UsingConfigurationManager.GetAppConfiguration()
Exit Select
Case "5"
' Show how to use ConnectionStrings.
UsingConfigurationManager.ReadConnectionStrings()
Exit Select
Case "6"
' Show how to use OpenMappedExeConfiguration.
UsingConfigurationManager.MapExeConfiguration()
Exit Select
Case "7"
' Show how to use OpenMappedMachineConfiguration.
UsingConfigurationManager.MapMachineConfiguration()
Exit Select
Case Else
' DisplayUserMenu();
Exit Select
End Select
DisplayUserMenu()
Console.Write("> ")
selection = Console.ReadLine()
End While
End Sub
End Class
#End Region
End Namespace