Udx.IndexedDB.Blazor 2022.6.15

**UdxFramework

Udx.IndexedDB.Blazor

An easy way to interact with IndexedDB and make it feel like EF Core but async.

NuGet installation

The NuGet package is at: https://www.nuget.org/packages/Udx.IndexedDB.Blazor

Either install it from command line:

PM> Install-Package Udx.IndexedDB.Blazor

Features

• Connect and create database
• Add record
• Remove record
• Edit record
• Search record

How to use

1. Add TG.Blazor.IndexedDB/indexedDb.Blazor.js to your index.html

<script src="_content/TG.Blazor.IndexedDB/indexedDb.Blazor.js"></script>

2. Register IndexedDbFactory as a service.

services.AddSingleton<IIndexedDbFactory, IndexedDbFactory>();

• IIndexedDbFactory is used to create the database connection and will create the database instance for you.

• IndexedDbFactory requires an instance of IJSRuntime which should normally already be registered.

3. Create any code first database model and inherit from IndexedDb. Only properties with the type IndexedSet<> will be used, any other properties will be ignored.

 public class ExampleDb : Udx.IndexedDB.Blazor.IndexedDb
    {
        public ExampleDb(IJSRuntime jSRuntime, string name, int version) : base(jSRuntime, name, version) { }

        public IndexedSet<Person> People { get; set; }
        public IndexedSet<Dog> Dog { get; set; }
    }

• Your model (eg. Person) should contain an Id property or a property marked with the Key attribute.

 public class Person
    {
        [Key]
        public long Id { get; set; }

        public string FirstName { get; set; }

        public string LastName { get; set; }

        [ForeignKey(nameof(DogId))]
        [Browsable(false)]
        public Dog Dog { get; set; } = new Dog()
        {
            Id = 10,
            Name = "IndexedDB"
        };

        public long DogId { get; set; }
    }

    public class Dog
    {
        public long Id { get; set; }
        public string Name { get; set; }
    }

4. Now you can start using your database.

• Usage in Razor via inject: @inject IIndexedDbFactory DbFactory

Adding records

using (var db = await this.DbFactory.Create<ExampleDb>())
        {
            for (int i = 0; i < 10; i++)
            {
                var p = new Person()
                    {
                        FirstName = Guid.NewGuid().ToString(),
                        LastName = Guid.NewGuid().ToString(),
                        DogId = i,
                        Dog = new Dog
                        {
                            Id = i,
                            Name = $"dog {i}"
                        }

                    };
                db.People.Add(p);
                db.Dog.Add(p.Dog);

            }
            await db.SaveChanges();
        }

Removing records

To remove an element it is faster to use an already created reference. You should also be able to remove an object only by it's Id but you have to use the .Remove(object) method (eg. .Remove(new object() { Id = 1 }))

using (var db = await this.DbFactory.Create<ExampleDb>())
{
  var firstPerson = db.People.First();
  db.People.Remove(firstPerson);
  await db.SaveChanges();
}

Modifying records

using (var db = await this.DbFactory.Create<ExampleDb>())
{
  var personWithId1 = db.People.Single(x => x.Id == 1);
  personWithId1.FirstName = "This is 100% a first name";
  await db.SaveChanges();
}

Search records

  using (var db = await this.DbFactory.Create<ExampleDb>())
        {
            listPeople = from p in db.People
                         join d in db.Dog on p.DogId equals d.Id
                         where d.Name.Contains("dog")
                         select new Person
                             {
                                 Id = p.Id,
                                 FirstName = p.FirstName,
                                 LastName = p.LastName,
                                 DogId = p.DogId,
                                 Dog = d
                             };
        }

License

Original license. Original license.

Site

Udx Udx.com.cn

Licensed under the MIT license.