How to create fully fledged C# custom actions
The method presented in this article is no longer recommended. The new method is
described in this article: How to create a .NET Custom Action
The following article uses options that are available starting with the Professional edition and project type.
The installation process can be controlled using Custom Actions. They can be dynamic linked libraries, Visual Basic scripts or JavaScript files. A custom action written in C# will generate a dynamic linked library file (DLL).
Tools required
In order to create a custom action in C# the WiX Toolset is required to be installed on the developer machine. Once downloaded and installed, the toolset will add all necessary modules enabling you to create C# custom actions from Microsoft Visual Studio.
Wix v4 can be used only for Visual Studio 2022 and Visual Studio 2019, for older versions of Visual Studio please use Wix Toolset 3.5.
Creating a C# custom actions project
Once all the necessary tools are installed, the following steps must be followed:
1. Start Microsoft Visual Studio
2. From the Menu bar select “File
> New Project”
3. From the "New Project" dialog select
“WiX” project type and “C# Custom Action
Project”
By default, the new project will generate a simple custom action that will write some text in the installer log:
using System; using System.Collections.Generic; using System.Linq; using System.Text; using Microsoft.Deployment.WindowsInstaller; namespace CustomAction1 { public class CustomActions { [CustomAction] public static ActionResult CustomAction1(Session session) { session.Log("Begin CustomAction1"); // Here you can write your own custom action code return ActionResult.Success; } } }
4. Based on the above example, CustomAction1 is the name of the custom action function. This name can be customized when writing your own custom action.
Generate the custom action file
1. From the Menu bar select the “Build > Build Solution”
option.
2. This will generate two DLL files:
CustomAction1.dll and
CustomAction1.CA.dll
3. The
CustomAction1.CA.dll file is the one that holds the C# custom
action which will be used in Advanced Installer.
Integrate the C# custom action in Advanced Installer
1. Select the CustomAction1.CA.dll file and add it to your
Advanced Installer project
2. Go to Custom Actions Page, add a Custom Actions List“Call function from
attached native DLL” custom action with sequence from Add Custom Action Tab or
the toolbar and select CustomAction1.CA.dll
3. In the
"Function Name" field from the "Custom Action Properties" view select
CustomAction1
4. Build the project and test it
Get / Set properties from C# custom action
The following example demonstrates how to get or set an installer public property from a C# custom action:
public static ActionResult CustomAction1(Session session) { // sending message to installation log session.Log("Begin CustomAction1"); // getting a property YourVariable = session["YOUR_PROPERTY"]; // setting a property session["YOUR_PROPERTY"] = "YOUR_VALUE"; return ActionResult.Success; }
Below is a link to a short video depicting the steps explained above.
Debug C# custom action
1. A simple method to debug your custom action code is to use the Debugger.Launch(); function call at the beginning of your custom action:
public static ActionResult CustomAction1(Session session) { // attaching the debugger Debugger.Launch(); // sending message to installation log session.Log("Begin CustomAction1"); . . .
2. Add some code for displaying a message box at the beginning of your custom action:
public static ActionResult CustomAction1(Session session) { // display message to allow attaching the debugger MessageBox.Show("Please attach a debugger to rundll32.exe.", "Attach"); // sending message to installation log session.Log("Begin CustomAction1"); . . .
1. Since you will use MessageBox, make sure you have a reference to
System.Windows.Forms.dll
2. Add a breakpoint on the next line of code, after your
message box code
3. Rebuild your custom action project with Visual Studio
4.
Rebuild your Advanced Installer project
5. Run the installation using "Run and Log"
from Advanced Installer
6. When the message box displays, go to Visual Studio
project > Tools > Attach to Process…
7. From the Available Processes list select the
process with the name "rundll32.exe" and title "Attach"
8. Click Ok on the message
box in your installation
9. The breakpoint you set earlier should now be activated
in VS
While debugging the custom action after implementing the above steps, you can observe the property changes in the Log pane of Advanced Installer.
Below is a link to a short video depicting the steps explained above.