PowerShell is a great tool. It helps in SharePoint administration and tasks automation. Today I needed to provision a webpart on many similar pages. This third-party webpart’s constructor instantiates a dataaccess service and uses a connectionstring which is stored in the web.config file. So the webpart creation failed until I found a way to load the configuration into powershell. First you can create a simple file powershell.exe.config, put it into $pshome (C:\Windows\System32\WindowsPowerShell\v1.0). In that file you can specify the connectionstring in the same way like in the web.config (or app.config). But it is not secure: the connectionstring can be changed in the future, and you really don’t want to copy your connectionstrings around. So there is a better way: Check out Ohad Israeli’s blog post about how a configuration file can be bound dynamically in a .net assembly: Binding to a custom App.Config file. In PowerShell you can do the same, all we need is to modify the syntax: StackOverflow: Powershell Calling .NET Assembly that uses App.config:

An alternative to store key-value paired properties in appSettings in web.config we can use Sharepoint_config database by creating our own SPPersistedObject.  First we have to create a class which inherits from SPPersistedObject and decorate its properties with [Persisted]:

namespace Takana.SharePoint
{
    public class Settings: SPPersistedObject
    {
        \[Persisted\]
        public string DbConString;
 
        public LinkCheckerPersistedSettings() { }
        public LinkCheckerPersistedSettings(string name, SPPersistedObject parent) : base(name, parent) { }
    }
}
```Then we must create such an object. Let's do it in Powershell:

if(-not(Get-PSSnapin | Where { $_.Name -eq “Microsoft.SharePoint.PowerShell”})) { Add-PSSnapin Microsoft.SharePoint.PowerShell }

SPWebConfigModification. Some links to start with: http://panvega.wordpress.com/2009/09/02/using-spwebconfigmodification-within-a-feature-receiver/ http://www.onedotnetway.com/get-name-of-current-executing-assembly-in-c/ http://blogs.devhorizon.com/reza/?p=459 http://ikarstein.wordpress.com/2010/09/02/add-web-config-modification-with-powershell-spwebconfigmodification/ http://msdn.microsoft.com/en-us/library/bb861909.aspx

public override void FeatureActivated(SPFeatureReceiverProperties properties)
{
	var webapp = parent as SPWebApplication;
	if (webapp != null)
	{
		var mod1 = GetWebControlsConfigMod();
		webapp.WebConfigModifications.Add(mod1);
		var mod2 = GetConStringConfigMod();
		webapp.WebConfigModifications.Add(mod2);
		SaveChanges(webapp);
	}
	else
	{
		Log.Warning("no modifications to webapp are done");
	}
}

public override void FeatureDeactivating(SPFeatureReceiverProperties properties)
{
	var webapp = parent as SPWebApplication;
	if (webapp != null)
	{
		var mod = GetWebControlsConfigMod();
		var modsCollection = webapp.WebConfigModifications;
		var modToDelete =
			(from m in modsCollection
			 where m.Value.Equals(mod.Value, StringComparison.InvariantCultureIgnoreCase)
			 select m).FirstOrDefault();
		if (modToDelete != null)
		{
			modsCollection.Remove(modToDelete);
			SaveChanges(webapp);
		}
	}
}
private static void SaveChanges(SPPersistedObject webapp)
{
	var service = webapp.Farm.Services.GetValue();
	service.ApplyWebConfigModifications();
	webapp.Update();
}

private static SPWebConfigModification GetWebControlsConfigMod()
{
	var assembly = System.Reflection.Assembly.GetAssembly(typeof(WebControls.OfficeEditor));
	var ass = assembly.FullName;
	var @namespace = assembly.GetName().Name + ".WebControls";
	var value = string.Format("", ass,
							  @namespace);
	const string path = "configuration/SharePoint/SafeControls";
	var mod = new SPWebConfigModification
	{
		Path = path,
		Name = "JustaName1",
		Sequence = 0,
		Owner = @namespace,
		Type = SPWebConfigModification.SPWebConfigModificationType.EnsureChildNode,
		Value = value
	};
	return mod;
}

private static SPWebConfigModification GetConStringConfigMod()
{
	const string name = "ContosoConString";
	const string conString =
		"Data Source=db.contoso.com;Initial Catalog=contoso\_db;Persist Security Info=True;User ID=contoso\_Contributor;Password=contoso";
	var mod = new SPWebConfigModification
	  {
		  Name = "JustaName2",
		  Path = "configuration/connectionStrings",
		  Owner = "contoso\_connectionstrings",
		  Type = SPWebConfigModification.SPWebConfigModificationType.EnsureChildNode,
		  Value = String.Format("", name, conString)
	  };
	return mod;
}
```Powershell:

#ADDING asnp microsoft.sharepoint.powershell $url = “http://contoso” $app = Get-SPWebApplication $url $name = “ContosoConString”; $conString = “Data Source=db.contoso.com;Initial Catalog=contoso_db;Persist Security Info=True;User ID=contoso_Contributor;Password=contoso”; $mod = new-object Microsoft.SharePoint.Administration.SPWebConfigModification $mod.Name = “JustName2” $mod.Path = “configuration/connectionStrings” $mod.Owner = “User Name” $mod.Type = 0 #for the enum value “SPWebConfigModification.SPWebConfigModificationType.EnsureChildNode” $mod.Value = ‘’ -f $name, $conString $app.WebConfigModifications.Add($mod) $service = [Microsoft.SharePoint.Administration.SPWebService]::ContentService $service.ApplyWebConfigModifications() $app.Update() #ADDING snapin asnp microsoft.sharepoint.powershell