It's useful if you have multiple installation files that you'll like the user to install in on step.
The Bootstrapper itself is a .exe installer file, it also may have .SED file which contains details of the contents of the .exe.
There are a few applications out there to generate a bootstrapper, the most simple I've seen is the an app called IEXpress.
Is actually installed on windows (System32/iexpress.exe).
This creates an installer, you tell it what files you wish it to include in the installation.
I've only played with this so far and it appears to me that the isntaller can only install upto 2 setup.exes. You can include as many files as you like, but the files cannot have the same name, because of this you will probably need to rename your setup.exes to something else because you cannot have 2 files with the same name.
After you've included all the files you wish to run the next step asks you which files you wish to run, at this stage it looks like you can only specify upto 2 .exe installer files (there maybe a way around this, by editing the .sed file afterwards).
Also the final step I recommend telling the bootstrapper to use full files paths, this seems to ensure it works.
In Visual Studio the BootStrapper is read in as an XML file. Visual Studio has a set BootStrapper XML file which it reads, below I will describe how to use this default bootstrapper and then I will describe how to create your own.
Using the BootStrapper in Visual Studio
Visual Studio also has a Bootstrapper, it's actually the Launch Conditions Editor in the Setup Project. The prerequisites are what your looking for, you'll see .NET is there by default.
By right clicking the Setup Project and bringing up the Properties dialog you'll a prerequisites button, this launches another dialog which lists the prerequisites, only the default ones are there.
There is a snag with this however you can to add your own you'll need to create your own BootStrapper XML file
Create your own BootStrapper file
There are 2 ways to create the XML file
1. Write the XML file yourself and copy to the correct location:
you'll need to follow the instructions in the .zip found in the BootStrapper SDK
2. You can use an Community UI (BMG) to write the bootstrapper for you (note the web installer doesn't work funnily enough, the msi does, the program can then be found at C:\Program Files\Microsoft\Bootstrapper Manifest Generator\BMG.exe).
It allows you to add .msi files, .exe files and apply conditions for them. It also installs the bootstrapper xml file for you after, this makes it available in Visual Studios Setup Project Prerequisite dialog that I mentioned earlier.
Here's a complete description of how to install you Custom Prerequisite.
Use the Visual Studio 2005 Bootstrapper to Kick-Start Your Installation - This article is the complete version and is not msdn, Also describe Custom bootstrapping.
Adding Custom Prerequisites.
MSBuild GenerateBootStrapper Task
After you've created your Visual Studio BootStrapper you can use it with MSBuild with the GenerateBootstrapper Task.
This MSBuild task allows you to include your custom prerequisite in any Visual Studio Project.
So if you wish to create a Bootstrapper for your installer using MSBuild it's the same thing as Adding Prerequisites to your Setup Project using the Project->Properties->Prerequisite dialog.
You'll still need to have your prerequisites created and installed beforehand.
Here's and example of a project to create a BootStrapper using 2 Prerequisites:
ComponentsLocation="Relative" Culture="en" FallbackCulture="en-IE" CopyComponents="True"
Path="C:\Program Files\Microsoft Visual Studio 8\SDK\v2.0\Bootstrapper" />
<ProductName>.NET Framework 2.0</ProductName>
We're creating a BootStrapper called MyInstaller.msi.
We're setting our main Installer (the one whose Gui appears) to be "MyOriginalInstaller.msi".
We include this same main installer "MyOriginalInstaller.msi" in the current project, it appears that it must be found in the current project in order for this to work.
We include to pre-requisites which get installed beforehand, their ProductName must be identical to the folder name that appears in their installation location
C:\Program Files\Microsoft Visual Studio 8\SDK\v2.0\BootStrapper\Packages
C:\Program Files\Microsoft Visual Studio 8\SDK\v2.0\BootStrapper\Packages\ProjectAggregator2.msi\
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