LinkManager.Provider is deprecated in Sitecore 9, how to get the default provider then?

Question

The following code works in Sitecore 8.2 but not in Sitecore 9:

var provider = LinkManager.Provider;

The Provider property is not available anymore in Sitecore 9 Sitecore.Kernel, what should I use instead?

Answer 1

After digging into the new Sitecore.Kernel assembly I have found the following way to get the default LinkProvider or your custom with the following appraches:

To get default Sitecore.Links.LinkProvider:

var defaultProvider = ServiceLocator.GetRequiredResetableService<ProviderHelper<Sitecore.Links.LinkProvider, LinkProviderCollection>>()?.Value?.Provider;

To get your custom YourNamespace.LinkProvider:

var customProvider = ServiceLocator.GetRequiredResetableService<ProviderHelper<Sitecore.Links.LinkProvider, LinkProviderCollection>>()?.Value?.Provider as YourNamespace.LinkProvider;

As below in the comments Pete and Mark pointed out that the ServiceLocator is an antipattern so I gave a try to do it with dependency injection, and it works. The following example shows, how you can use it with ItemResolver and DI:

public class ItemResolver : HttpRequestProcessor
{
    protected readonly ProviderHelper<Sitecore.Links.LinkProvider, LinkProviderCollection> providerHelper;

    public ItemResolver(ProviderHelper<Sitecore.Links.LinkProvider, LinkProviderCollection> providerHelper)
    {
        this.providerHelper = providerHelper;
    }

    private Sitecore.Links.LinkProvider GetSitecoreLinkProvider()
    {
        return this.providerHelper?.Provider;
    }

    private YourNamespace.LinkProvider GetCustomLinkProvider()
    {
        return this.providerHelper?.Provider as YourNamespace.LinkProvider;
    }
}

Configuration:

<pipelines>
  <httpRequestBegin>
    <processor type="YourNamespace.ItemResolver, YourNamespace" resolve="true" />
  </httpRequestBegin>
</pipelines>