Reputation: 4885
I'm trying to find the best solution to have a local database in my WP8.1 application.
I'm using the standard WP8.1 (non-SL) and Visual Studio 2013.
I've looked into SQLite but I couldn't manage to get it to work on my application/Visual Studio.
If I can use SQLite, I need someone to point me out the way to go. Else, please refer me the best solution.
Thanks in advance!
Upvotes: 1
Views: 301
Reputation: 11570
Here's a repository class that leverages SQLite:
public class ContactsRepository : IContactsRepository
{
SQLiteAsyncConnection _connection = null;
static ContactsRepository _repository = null;
private ContactsRepository()
{
}
public async Task Initialize()
{
_connection = new SQLiteAsyncConnection(Constants.DATABASE_FILE_NAME);
await EnsureTableExist<ContactReference>(_connection);
}
public static ContactsRepository Instance
{
get
{
if (_repository == null)
{
_repository = new ContactsRepository();
}
return _repository;
}
}
public async Task Add(Category category, Contact contact)
{
var result = await _connection.Table<ContactReference>().Where(c => c.ContactId == contact.Id).FirstOrDefaultAsync();
if (result != null)
{
result.CategoryName = category.Name;
await _connection.UpdateAsync(result);
}
else
{
await _connection.InsertAsync(new ContactReference()
{
CategoryName = category.Name,
ContactId = contact.Id
});
}
}
public async Task Update(Category category, Contact contact)
{
var result = await _connection.Table<ContactReference>().Where(c => c.ContactId == contact.Id).FirstOrDefaultAsync();
Debug.Assert(result != null);
if (result == null)
{
throw new Exception("Unable to update category. Candidate not found");
}
if (result != null)
{
result.CategoryName = category.Name;
await _connection.UpdateAsync(result);
}
}
public async Task<ObservableCollection<Contact>> Get(string categoryName)
{
var result = new ObservableCollection<Contact>();
var query = _connection.Table<ContactReference>().Where(c => c.CategoryName == categoryName);
var queryResult = await query.ToListAsync();
foreach(var contact in queryResult)
{
var phoneContacts = ResourceLocator.Instance[typeof(ObservableCollection<Contact>)] as ObservableCollection<Contact>;
var phoneContact = phoneContacts.Where(c => c.Id == contact.ContactId).FirstOrDefault();
Debug.Assert(phoneContact != null);
if (phoneContact != null)
{
result.Add(phoneContact);
}
}
return result;
}
public async Task<ObservableCollection<ContactReference>> Get()
{
var result = new ObservableCollection<ContactReference>();
var query = _connection.Table<ContactReference>();
var queryResult = await query.ToListAsync();
foreach (var contact in queryResult)
{
result.Add(contact);
}
return result;
}
private async Task EnsureTableExist<T>(SQLiteAsyncConnection connection) where T : new()
{
bool noTableExists = false;
try
{
var query = await connection.Table<T>().FirstOrDefaultAsync();
}
catch (SQLiteException ex)
{
if (ex.Message.Contains("no such table"))
{
noTableExists = true;
}
}
if (noTableExists)
{
await connection.CreateTableAsync<T>();
}
}
}
Upvotes: 0