asked on

Overwirting a value in the app.config

VB.NET 2005

<connectionStrings>
<add name="Test.My.MySettings.ConnectrionString" connectionString="Data Source=(local);Initial Catalog=;User ID=;Password="
providerName="System.Data.SqlClient" />
</connectionStrings>

I want to overwrite a connectionstring in the app.config fiel

Dim asm As Assembly = Assembly.GetExecutingAssembly
Dim fi As FileInfo = New FileInfo(asm.Location + ".config")

Dim sConnectionString As String = "Data Source=*;Initial Catalog=;User ID=;Password="
Dim sNewConnectionString As String = sConnectionString.Replace("*", serverName)

' Loads the config file into the XML DOM.
Dim doc As New System.Xml.XmlDataDocument
doc.Load(fi.FullName)

' Finds the right node and change it to the new value.
Dim node As XmlNode
For Each node In doc.Item("configuration").Item("connectionStrings")
If node.Name = "add" Then
>>> UNSURE WHAT TO DO HERE

I used to use

If Node.Name = "add" Then
If Node.Attributes.GetNamedItem("key").Value = "cn" Then
Node.Attributes.GetNamedItem("value").Value = newCn

but these are no longer supported and the app.config file has changed

End If
Next node

' Write out the new config file.
doc.Save(fi.FullName)

Dirk Haest

Runtime Web.config / App.config Editing
http://www.eggheadcafe.com/articles/20030907.asp

ASKER CERTIFIED SOLUTION

drichards

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drichards

I suppose I should have put up VB code for this one...

Dim cfg As Configuration = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)
cfg.ConnectionStrings.ConnectionStrings("Test.My.MySettings.ConnectrionString").ConnectionString = "Data Source=localhost;Initial Catalog=;User ID=me;Password=password"
cfg.AppSettings.Settings.Add("newKey", "newValue")
cfg.AppSettings.Settings.Remove("myOtherConfig")
cfg.AppSettings.Settings("myConfig").Value = "modifiedConfigValue"
cfg.Save()

rocky050371

ASKER

It was fine, worked a treat

drichards

Also, if you run this in Visual Studio, don't be surprised if the <project>.exe.config is not changed when you are finished. In C# the environment leaves it changed on disk, but VB seems to replace it with the app.config source when the program is complete. If you want to see the resulting config file, you have to run the exe outside of the Visual Studio environment. And if you run it in the debugger, it uses the <project>.vshost.exe.config and not the <project>.exe.config.