FileDependency Class

Definition

Namespace

Cuemon.Runtime

Assemblies

Cuemon.Core.dll

Source

src/Cuemon.Core/Runtime/FileDependency.cs

Provides a way to monitor any changes occurred to one or more files while notifying subscribing objects.

public class FileDependency : Dependency, IDependency

Inheritance

object

Dependency

FileDependency

Implements

IDependency

Inherited Members

Dependency.DependencyChanged

Dependency.BreakTieOnChanged

Dependency.UtcLastModified

Dependency.HasChanged

Dependency.SetUtcLastModified(DateTime)

Dependency.OnDependencyChangedRaised(DependencyEventArgs)

Dependency.Start()

Dependency.StartAsync()

Dependency.OnWatcherChanged(object, WatcherEventArgs)

Examples

FileDependency defers FileWatcher creation until monitoring begins by accepting a Lazy<FileWatcher> factory. This example creates a temporary settings.json file, wraps a FileWatcher in a Lazy<> with a 500ms polling period, and passes it to FileDependency with breakTieOnChanged: true. Key steps include checking lazyWatcher.IsValueCreated before and after StartAsync to confirm deferred creation, subscribing to DependencyChanged, and inspecting HasChanged after signaling. Console output shows the watcher creation status, BreakTieOnChanged value, and the changed state.

using System;
using System.IO;
using System.Threading.Tasks;
using Cuemon.Runtime;

namespace MyApp.Examples;

public static class FileDependencyExample
{
    public static async Task DemonstrateAsync()
    {
        string filePath = Path.Combine(Environment.CurrentDirectory, "settings.json");
        File.WriteAllText(filePath, "{ }");

        var lazyWatcher = new Lazy<FileWatcher>(() => new FileWatcher(filePath, false, options =>
        {
            options.Period = TimeSpan.FromMilliseconds(500);
        }));

        var dependency = new FileDependency(lazyWatcher, breakTieOnChanged: true);
        dependency.DependencyChanged += static (_, e) => Console.WriteLine(e.UtcLastModified.ToString("O"));

        Console.WriteLine(lazyWatcher.IsValueCreated);
        Console.WriteLine(dependency.BreakTieOnChanged);

        await dependency.StartAsync();

        Console.WriteLine(lazyWatcher.IsValueCreated);
        Console.WriteLine(dependency.HasChanged);
    }
}

Constructors

Name	Description
FileDependency(IEnumerable<Lazy<FileWatcher>>, bool)	Initializes a new instance of the FileDependency class.
FileDependency(Lazy<FileWatcher>, bool)	Initializes a new instance of the FileDependency class.

See Also

Dependency