Question

My program is supposed to be installed to a path that recorded in registry. If the registry key is not found, then install to another(default) path.

For example, I’d like to have something like:

<Property Id="MYINSTALLDIR">
    <RegistrySearch Id='MyRegistry' Type='raw' Root='HKCU' Key='Software\MyApp\Foo' Name='InstallDir' />
    if not found, then set "MYINSTALLDIR" to "D:\working\defaultApps"
</Property>    

How should I write my wxs file to make this happen?

EDIT:

The problem now is:

if not found in registry, then set "MYINSTALLDIR" to LocalAppDataFolder 

I tried

<Property Id="MYINSTALLDIR" Value="LocalAppDataFolder">
    <RegistrySearch Id='MyRegistry' Type='raw' Root='HKCU' Key='Software\MyApp\Foo' Name='InstallDir' />
</Property>

But error returned:

Error 1606. Could not access network location LocalAppDataFolder.

Answer 1

From memory the example below should work. If no value is found for the search, the property gets the default value. It’s only overwritten if the search succeeds.

<Property Id="MYINSTALLDIR" Value="Default Property Value">
    <RegistrySearch Id='MyRegistry' Type='raw' Root='HKCU' Key='Software\MyApp\Foo' Name='InstallDir' />
</Property>