Search Results

Search found 32789 results on 1312 pages for 'object relational mapping'.

Page 203/1312 | < Previous Page | 199 200 201 202 203 204 205 206 207 208 209 210  | Next Page >

• RuntimeError: maximum recursion depth exceeded while calling a Python object

  - by Bilal Basharat

  this error arises when i try to run the following test case which is written in models.py of my django app named 'administration' : from django.test import Client, TestCase from django.core import mail class ClientTest( TestCase ): fixtures = [ 'testdata.json' ] def test_get_register( self ): response = self.client.get( '/accounts/register/', {} ) self.assertEqual( response.status_code, 200 ) the error arises at this line specifically: response = self.client.get( '/accounts/register/', {} ) my django version is 1.2.1 and python 2.6 and satchmo version is 0.9.2-pre hg-unknown. I code in windows platform(xp sp2). The command to run test case is: python manage.py test administration the complete error log is as follow: site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 121, in by_host site = by_host(host=host[4:], id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 124, in by_host site = by_host(host = 'www.%s' % host, id_only=id_only) File "build\bdist.win32\egg\threaded_multihost\sites.py", line 101, in by_host site = Site.objects.get(domain=host) File "C:\django\django\db\models\manager.py", line 132, in get return self.get_query_set().get(*args, **kwargs) File "C:\django\django\db\models\query.py", line 336, in get num = len(clone) File "C:\django\django\db\models\query.py", line 81, in __len__ self._result_cache = list(self.iterator()) File "C:\django\django\db\models\query.py", line 269, in iterator for row in compiler.results_iter(): File "C:\django\django\db\models\sql\compiler.py", line 672, in results_iter for rows in self.execute_sql(MULTI): File "C:\django\django\db\models\sql\compiler.py", line 717, in execute_sql sql, params = self.as_sql() File "C:\django\django\db\models\sql\compiler.py", line 65, in as_sql where, w_params = self.query.where.as_sql(qn=qn, connection=self.connection) File "C:\django\django\db\models\sql\where.py", line 91, in as_sql sql, params = child.as_sql(qn=qn, connection=connection) File "C:\django\django\db\models\sql\where.py", line 94, in as_sql sql, params = self.make_atom(child, qn, connection) File "C:\django\django\db\models\sql\where.py", line 141, in make_atom lvalue, params = lvalue.process(lookup_type, params_or_value, connection) File "C:\django\django\db\models\sql\where.py", line 312, in process connection=connection, prepared=True) File "C:\django\django\db\models\fields\subclassing.py", line 53, in inner return func(*args, **kwargs) File "C:\django\django\db\models\fields\subclassing.py", line 53, in inner return func(*args, **kwargs) File "C:\django\django\db\models\fields\__init__.py", line 323, in get_db_prep _lookup return [self.get_db_prep_value(value, connection=connection, prepared=prepar ed)] File "C:\django\django\db\models\fields\subclassing.py", line 53, in inner return func(*args, **kwargs) File "C:\django\django\db\models\fields\subclassing.py", line 53, in inner return func(*args, **kwargs) RuntimeError: maximum recursion depth exceeded while calling a Python object ---------------------------------------------------------------------- Ran 7 tests in 48.453s FAILED (errors=1) Destroying test database 'default'...

  Read the article

• What's the best way to expose a Model object in a ViewModel?

  - by Angel

  In a WPF MVVM application, I exposed my model object into my viewModel by creating an instance of Model class (which cause dependency) into ViewModel. Instead of creating separate VM properties, I wrap the Model properties inside my ViewModel Property. My model is just an entity framework generated proxy class: public partial class TblProduct { public TblProduct() { this.TblPurchaseDetails = new HashSet<TblPurchaseDetail>(); this.TblPurchaseOrderDetails = new HashSet<TblPurchaseOrderDetail>(); this.TblSalesInvoiceDetails = new HashSet<TblSalesInvoiceDetail>(); this.TblSalesOrderDetails = new HashSet<TblSalesOrderDetail>(); } public int ProductId { get; set; } public string ProductCode { get; set; } public string ProductName { get; set; } public int CategoryId { get; set; } public string Color { get; set; } public Nullable<decimal> PurchaseRate { get; set; } public Nullable<decimal> SalesRate { get; set; } public string ImagePath { get; set; } public bool IsActive { get; set; } public virtual TblCompany TblCompany { get; set; } public virtual TblProductCategory TblProductCategory { get; set; } public virtual TblUser TblUser { get; set; } public virtual ICollection<TblPurchaseDetail> TblPurchaseDetails { get; set; } public virtual ICollection<TblPurchaseOrderDetail> TblPurchaseOrderDetails { get; set; } public virtual ICollection<TblSalesInvoiceDetail> TblSalesInvoiceDetails { get; set; } public virtual ICollection<TblSalesOrderDetail> TblSalesOrderDetails { get; set; } } Here is my ViewModel: public class ProductViewModel : WorkspaceViewModel { #region Constructor public ProductViewModel() { StartApp(); } #endregion //Constructor #region Properties private IProductDataService _dataService; public IProductDataService DataService { get { if (_dataService == null) { if (IsInDesignMode) { _dataService = new ProductDataServiceMock(); } else { _dataService = new ProductDataService(); } } return _dataService; } } //Get and set Model object private TblProduct _product; public TblProduct Product { get { return _product ?? (_product = new TblProduct()); } set { _product = value; } } #region Public Properties public int ProductId { get { return Product.ProductId; } set { if (Product.ProductId == value) { return; } Product.ProductId = value; RaisePropertyChanged("ProductId"); } } public string ProductName { get { return Product.ProductName; } set { if (Product.ProductName == value) { return; } Product.ProductName = value; RaisePropertyChanged(() => ProductName); } } private ObservableCollection<TblProduct> _productRecords; public ObservableCollection<TblProduct> ProductRecords { get { return _productRecords; } set { _productRecords = value; RaisePropertyChanged("ProductRecords"); } } //Selected Product private TblProduct _selectedProduct; public TblProduct SelectedProduct { get { return _selectedProduct; } set { _selectedProduct = value; if (_selectedProduct != null) { this.ProductId = _selectedProduct.ProductId; this.ProductCode = _selectedProduct.ProductCode; } RaisePropertyChanged("SelectedProduct"); } } #endregion //Public Properties #endregion // Properties #region Commands private ICommand _newCommand; public ICommand NewCommand { get { if (_newCommand == null) { _newCommand = new RelayCommand(() => ResetAll()); } return _newCommand; } } private ICommand _saveCommand; public ICommand SaveCommand { get { if (_saveCommand == null) { _saveCommand = new RelayCommand(() => Save()); } return _saveCommand; } } private ICommand _deleteCommand; public ICommand DeleteCommand { get { if (_deleteCommand == null) { _deleteCommand = new RelayCommand(() => Delete()); } return _deleteCommand; } } #endregion //Commands #region Methods private void StartApp() { LoadProductCollection(); } private void LoadProductCollection() { var q = DataService.GetAllProducts(); this.ProductRecords = new ObservableCollection<TblProduct>(q); } private void Save() { if (SelectedOperateMode == OperateModeEnum.OperateMode.New) { //Pass the Model object into Dataservice for save DataService.SaveProduct(this.Product); } else if (SelectedOperateMode == OperateModeEnum.OperateMode.Edit) { //Pass the Model object into Dataservice for Update DataService.UpdateProduct(this.Product); } ResetAll(); LoadProductCollection(); } #endregion //Methods } Here is my Service class: class ProductDataService:IProductDataService { /// <summary> /// Context object of Entity Framework model /// </summary> private MaizeEntities Context { get; set; } public ProductDataService() { Context = new MaizeEntities(); } public IEnumerable<TblProduct> GetAllProducts() { using(var context=new R_MaizeEntities()) { var q = from p in context.TblProducts where p.IsDel == false select p; return new ObservableCollection<TblProduct>(q); } } public void SaveProduct(TblProduct _product) { using(var context=new R_MaizeEntities()) { _product.LastModUserId = GlobalObjects.LoggedUserID; _product.LastModDttm = DateTime.Now; _product.CompanyId = GlobalObjects.CompanyID; context.TblProducts.Add(_product); context.SaveChanges(); } } public void UpdateProduct(TblProduct _product) { using (var context = new R_MaizeEntities()) { context.TblProducts.Attach(_product); context.Entry(_product).State = EntityState.Modified; _product.LastModUserId = GlobalObjects.LoggedUserID; _product.LastModDttm = DateTime.Now; _product.CompanyId = GlobalObjects.CompanyID; context.SaveChanges(); } } public void DeleteProduct(int _productId) { using (var context = new R_MaizeEntities()) { var product = (from c in context.TblProducts where c.ProductId == _productId select c).First(); product.LastModUserId = GlobalObjects.LoggedUserID; product.LastModDttm = DateTime.Now; product.IsDel = true; context.SaveChanges(); } } } I exposed my model object in my viewModel by creating an instance of it using new keyword, also I instantiated my DataService class in VM. I know this will cause a strong dependency. So: What's the best way to expose a Model object in a ViewModel? What's the best way to use DataService in VM?

  Read the article

• Unstructured Data - The future of Data Administration

  Some have claimed that there is a problem with the way data is currently managed using the relational paradigm do to the rise of unstructured data in modern business. PCMag.com defines unstructured data as data that does not reside in a fixed location. They further explain that unstructured data refers to data in a free text form that is not bound to any specific structure. With the rise of unstructured data in the form of emails, spread sheets, images and documents the critics have a right to argue that the relational paradigm is not as effective as the object oriented data paradigm in managing this type of data. The relational paradigm relies heavily on structure and relationships in and between items of data. This type of paradigm works best in a relation database management system like Microsoft SQL, MySQL, and Oracle because data is forced to conform to a structure in the form of tables and relations can be derived from the existence of one or more tables. These critics also claim that database administrators have not kept up with reality because their primary focus in regards to data administration deals with structured data and the relational paradigm. The relational paradigm was developed in the 1970’s as a way to improve data management when compared to standard flat files. Little has changed since then, and modern database administrators need to know more than just how to handle structured data. That is why critics claim that today’s data professionals do not have the proper skills in order to store and maintain data for modern systems when compared to the skills of system designers, programmers , software engineers, and data designers  due to the industry trend of object oriented design and development. I think that they are wrong. I do not disagree that the industry is moving toward an object oriented approach to development with the potential to use more of an object oriented approach to data.   However, I think that it is business itself that is limiting database administrators from changing how data is stored because of the potential costs, and impact that might occur by altering any part of stored data. Furthermore, database administrators like all technology workers constantly are trying to improve their technical skills in order to excel in their job, so I think that accusing data professional is not just when the root cause of the lack of innovation is controlled by business, and it is business that will suffer for their inability to keep up with technology. One way for database professionals to better prepare for the future of database management is start working with data in the form of objects and so that they can extract data from the objects so that the stored information within objects can be used in relation to the data stored in a using the relational paradigm. Furthermore, I think the use of pattern matching will increase with the increased use of unstructured data because object can be selected, filtered and altered based on the existence of a pattern found within an object.

  Read the article

• Can I use CodeSynthesis XSD (C++/Tree mapping) together with a GPLv3-licensed library?

  - by Erik Sjölund

  Is it possible to write an open source project that uses generated code from CodeSynthesis XSD (C++/Tree) and then link it to a third-party library that is licensed under the GPL version 3? Some background information: CodeSynthesis XSD is licensed under the GPL version 2 but with an extra FLOSS exception (http://www.codesynthesis.com/projects/xsd/FLOSSE). C++ source code generated from CodeSynthesis XSD (C++/Tree) needs to be linked against Xerces (http://xerces.apache.org/xerces-c/) that is licensed under the Apache License 2.0. Update I posted a similar question on the xsd-users mailing list two years ago but I didn't fully understand the answers. In that email thread, I wrote: I think it is the GPL version 3 software that doesn't allow itself be linked to software that can't be "relicensed" to GPL version 3 ( for instance GPL version 2 software ). That would also include XSD as the FLOSS exception doesn't give permission to "relicense" XSD to GPL version 3.

  Read the article

• Does having multiple URIs mapping to the same resource help SEO?

  - by Brian Wheeler

  Let's say I have a site with products that have tags, if each resource is available at GET '/products/tagged/:tag_list/:product_permalink' Could that be better for SEO than just one permalink? For example a product tagged "tea" and "coffee" would be available at GET '/products/tagged/tea/:product_permalink' GET '/products/tagged/coffee/:product_permalink' GET '/products/tagged/tea/coffee/:product_permalink' GET '/products/tagged/coffee/tea/:product_permalink' I would imagine that google would appreciate this because it gives multiple URIs with different levels of detail about the product, but I cant really be certain. Anyone have any direct knowledge on the topic? --EDIT-- As John Conde points, this is a horrible idea. What about having the links on my site link to a route such as GET '/products/tagged/:full_tag_list/:product_permalink', and then any time a user changes tags just have a HTTP moved permanently status to the new URL. Therefore duplicate URLs would be highly unlikely and mitigated by the proper response. Would this be better?

  Read the article

• What the Hekaton?

  - by Tony Davis

  Hekaton, the power behind SQL Server 2014′s In-Memory OLTP technology, is intended to make data operations run orders of magnitude faster on SQL Server. This works its magic partly by serving database workloads entirely from main memory, using memory-optimized table structures. It replaces the relational engine’s standard locking model with an optimistic concurrency model based on time-stamped row versions. Deeper down the Hekaton engine uses new, ‘latch free’ data structures. So far, so good, but performance improvements on this scale require a compromise, and the compromise is that these aren’t tables as we understand them. For the database developer, these differences are painful because they involve sacrificing some very important bits of the relational model. Most importantly, Hekaton tables don’t currently support FOREIGN KEY constraints or CHECK constraints, and you can’t put the checks in triggers because there aren’t any DML triggers either. Constraints allow a relational designer to enforce relational integrity and data integrity. Without them, of course, ‘bad data’ can get into our Hekaton tables. There is no easy way of preventing it. For several classes of database and data, this is a show-stopper. One may regard all these restrictions regretfully, seeing limited opportunity to try out Hekaton with current databases, but perhaps there is also a sudden glow of recognition. Isn’t this how we all originally imagined table variables were going to be, back in SQL 2005? And they have much the same restrictions. Maybe, instead of pretending that a currently-designed database can be ‘Hekatonized’ with a few mouse clicks, we should redesign databases for SQL 2014 to replace table variables with Hekaton tables, exploiting this technology for fast intermediate processing, and for the most part forget, for now, the idea of trying to convert our base relational tables into Hekaton tables. Few database developers would be averse to having their working tables running an order of magnitude faster, as long as it didn’t compromise the integrity of the data in the base tables.

  Read the article

• Parse DataSet via Reflection

  This article shows how to bind relational data model with object design model

  Read the article

• Are there any examples of a temporal field/object updater?

  - by Bryan Agee

  The system in question has numerous examples of temporal objects and fields--ones which are a certain variable at a certain point in time. An example of this would be someone's rate of pay--there are different answers depending on when you ask and what the constraints might be; eg, can there ever be more than one of a certain temporal object concurrently, etc. Ideally, there would be an object that handles those constraints when a new state/stateful object is introduced; when a new value is set, it would prevent creating negative ranges and overlaps. Martin Fowler has written some great material on this (such as this description of Temporal Objects) , but what I've found of it tends to be entirely theoretic, with no concrete implementations. PHP is the target language, but examples in any language would be most helpful.

  Read the article

• NoSQL

  - by NoReasoning

  Last night, (Tuesday, June 28), at the KC .NET User group meeting, George Westwater gave a terrific presentation on NoSQL. The best way to define it (the best way is to see George explain it, and he says he will record his presentation and make it available through his blog – link above)  is databases  that does not use relational technology. And his point, and this is true – I have been around awhile – is that non-relational databases have been used for over 50 years in the business. He points out that Wall Street firms have been using non-relational technology ever since they started using computers. IBM still fully supports IMS, now in version 11 (12 is in beta), because these firms are still using this product and will continue to do so for a long time. Of course, like a lot of computer business technology, there are a lot of new NoSQL products available these days, simply as a reaction to the problems of scaling relational databases for internet use. As a result, it almost looks as though NoSQL is something new. And there are a lot, I mean a LOT, I mean a L-O-T , of new products out there for this technology. The best resource to cover all of these products is http://nosql-database.org/, which has a huge listing of what is available. My interest in the subject is primarily due to my interest in Windows Azure and the fact that Windows Azure storage is all non-relational, even the table storage. It is very fascinating and most of all, far cheaper than using SQL Azure for storage in the “cloud."

  Read the article

• How do I pass an object location into a vertex shader?

  - by Greg Kassapidis

  I am using Blender Game Engine. I want to create a large flat plane, and deform it locally near a moving object. So far (despite being a beginner at shaders) I've written a vertex shader for the plane which moves the vertices to their correct positions (constant positions, for now). I cannot find a way to swap that constant location with an object's location updated every frame, while the shader is running. I am not even sure if it's possible. I only want to access a specific object's center from the shader.

  Read the article

• When mapping the surface of a sphere with tiles, how might you deal with polar distortion?

  - by clweeks

  It's easy to deal with the way locations interact on a clean Cartesian grid. It's just vanilla math. And you can kind of ignore the geometry of the sphere's surface for a bunch of it if you want to just truncate the poles or something. But I keep coming up with ideas for games where the polar space matters. Geo-coded ARGs and global roguelikes and stuff. I want square(ish?) locations -- reasonably representable by square tiles of the same size across the globe, anyway. This has to be a solved problem, right? What are the solutions? ETA: At the equator -- and assuming that your square locations are reasonably small, it's close enough to true that you can get away with having one square in the rows north and south of the most equatorial row. And you could probably get away with that by just hand-waving the difference up to like 45-degrees or so. But eventually, you need to have fewer squares in a pole-ward circumferential row. If I reduce the length of the row by one and offset the squares by 1/2 then they're just like hexes and it's relatively easy to do the coding to keep track of the connections. But as you get pole-ward, it gets more and more extreme. Projecting the surface of the world onto the surface of a cube is tempting. But I figured there must be more elegant solutions already in use. If I did the cube thing (not dissecting it further through geodesy) Are there any pros and cons related to placing the pole at the center of a face or at the vertex of three sides?

  Read the article

• How to detect whether an Object came to sleep at a specific position?

  - by Nils Riedemann

  I'm currently writing a small game with box2dweb and I need some direction for this: I'm throwing a Box and have to hit a specific place and trigger an event when the object that's been thrown isn't moving anymore, "fell asleep" so to say. What's the proper way / best practice for this? I'm currently thinking of asking the b2World whether an Object is within a specific AABB and then wait a few seconds, check if it's still there and then trigger the event. But this seems to me like the roundabout way and the object might still be moving inside of that AABB and eventually even drop out of the AABB.

  Read the article

• Efficient way of detecting a touched object in a game?

  - by Pin

  Imagine a Sims-like 2D game for a touch based mobile phone where one can interact with virtually any object in the scene. How can I efficiently detect which object is being touched by the player? In my short experience, looping through all the visible objects in the scene and checking if they're touched has so far done the job, but when there may be many many moving objects in the screen that sounds kind of inefficient isn't it? Keeping the visible moving objects list can consume time in itself as one may have to loop through all of them each frame. Other solutions I've thought are: Spatial hashing. Divide the screen as a grid and place the visible objects in the corresponding bucket. Detection of the clicked object is fast but there's additional overhead for placing the objects in the correct bucket each frame. Maintaining a quad-tree. Moving objects have to be rearranged all the time, the previous solution looks better. What is usually done in this case?

  Read the article

• how to serialize function depending on what instance of object calls it, if same instance call in a thread then do serialize else not

  - by LondonDreams

  I have a function which fetches and updates some record from db and I am trying to make sure each if the function is called by same instance of object(same Or different thread) then function should behave synchronized else its a call from different object instance function need not to be synchronized. I have tried it use a lock per client. That is, instead of synchronizing the method directly using explicit locking through lock objects using Map. function is like :- getAndUpdateMyHitCount(myObjId){ //go to db and get unique record by myObjId //fetch value , increment , save update } And this function may get call is same thread by different Or same object instance But as fetching and matching from Map is slow , Is there other optimized way to do this ? Found similar at this Question but dont feel that is optimized

  Read the article

• Could you give me an example of how to attach an object in Deleted state – I keep getting an exception [migrated]

  - by carewithl

  From MSDN : An object in the Deleted state can only be attached when the ObjectStateManager is already tracking the relationship instance. Could you give me an example of how to attach an object in the Deleted state. I tried the following and got "System.InvalidOperationException: The object being attached is in an added or deleted state. Relationships cannot be created for objects in this state". var contact = context.Contacts.First(); Console.WriteLine(contact.Addresses.Count()); // 2 var address = contact.Addresses.First(); context.Addresses.DeleteObject(address); contact.Addresses.Attach(address); // InvalidOperationException thank you

  Read the article

• Applying ServiceKnownTypeAttribute to WCF service with Spring

  - by avidgoffer

  I am trying to apply the ServiceKnownTypeAttribute to my WCF Service but keep getting the error below my config. Does anyone have any ideas? <object id="HHGEstimating" type="Spring.ServiceModel.ServiceExporter, Spring.Services"> <property name="TargetName" value="HHGEstimatingHelper"/> <property name="Name" value="HHGEstimating"/> <property name="Namespace" value="http://www.igcsoftware.com/HHGEstimating"/> <property name="TypeAttributes"> <list> <ref local="wcfErrorBehavior"/> <ref local="wcfSilverlightFaultBehavior"/> <object type="System.ServiceModel.ServiceKnownTypeAttribute, System.ServiceModel"> <constructor-arg name="type" value="IGCSoftware.HHG.Business.UserControl.AtlasUser, IGCSoftware.HHG.Business"/> </object> </list> </property> Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: Spring.Objects.Factory.ObjectCreationException: Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. Stack Trace: [ObjectCreationException: Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46'] Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolveInnerObjectDefinition(String name, String innerObjectName, String argumentName, IObjectDefinition definition, Boolean singletonOwner) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:300 Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolvePropertyValue(String name, IObjectDefinition definition, String argumentName, Object argumentValue) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:150 Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolveValueIfNecessary(String name, IObjectDefinition definition, String argumentName, Object argumentValue) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:112 Spring.Objects.Factory.Config.ManagedList.Resolve(String objectName, IObjectDefinition definition, String propertyName, ManagedCollectionElementResolver resolver) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Config\ManagedList.cs:126 Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolvePropertyValue(String name, IObjectDefinition definition, String argumentName, Object argumentValue) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:201 Spring.Objects.Factory.Support.ObjectDefinitionValueResolver.ResolveValueIfNecessary(String name, IObjectDefinition definition, String argumentName, Object argumentValue) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\ObjectDefinitionValueResolver.cs:112 Spring.Objects.Factory.Support.AbstractAutowireCapableObjectFactory.ApplyPropertyValues(String name, RootObjectDefinition definition, IObjectWrapper wrapper, IPropertyValues properties) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractAutowireCapableObjectFactory.cs:373 Spring.Objects.Factory.Support.AbstractAutowireCapableObjectFactory.PopulateObject(String name, RootObjectDefinition definition, IObjectWrapper wrapper) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractAutowireCapableObjectFactory.cs:563 Spring.Objects.Factory.Support.AbstractAutowireCapableObjectFactory.ConfigureObject(String name, RootObjectDefinition definition, IObjectWrapper wrapper) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractAutowireCapableObjectFactory.cs:1844 Spring.Objects.Factory.Support.AbstractAutowireCapableObjectFactory.InstantiateObject(String name, RootObjectDefinition definition, Object[] arguments, Boolean allowEagerCaching, Boolean suppressConfigure) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractAutowireCapableObjectFactory.cs:918 Spring.Objects.Factory.Support.AbstractObjectFactory.CreateAndCacheSingletonInstance(String objectName, RootObjectDefinition objectDefinition, Object[] arguments) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractObjectFactory.cs:2120 Spring.Objects.Factory.Support.AbstractObjectFactory.GetObjectInternal(String name, Type requiredType, Object[] arguments, Boolean suppressConfigure) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\AbstractObjectFactory.cs:2046 Spring.Objects.Factory.Support.DefaultListableObjectFactory.PreInstantiateSingletons() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Objects\Factory\Support\DefaultListableObjectFactory.cs:505 Spring.Context.Support.AbstractApplicationContext.Refresh() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\AbstractApplicationContext.cs:911 _dynamic_Spring.Context.Support.XmlApplicationContext..ctor(Object[] ) +197 Spring.Reflection.Dynamic.SafeConstructor.Invoke(Object[] arguments) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Reflection\Dynamic\DynamicConstructor.cs:116 Spring.Context.Support.RootContextInstantiator.InvokeContextConstructor(ConstructorInfo ctor) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextHandler.cs:550 Spring.Context.Support.ContextInstantiator.InstantiateContext() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextHandler.cs:494 Spring.Context.Support.ContextHandler.InstantiateContext(IApplicationContext parentContext, Object configContext, String contextName, Type contextType, Boolean caseSensitive, String[] resources) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextHandler.cs:330 Spring.Context.Support.ContextHandler.Create(Object parent, Object configContext, XmlNode section) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextHandler.cs:280 [ConfigurationErrorsException: Error creating context 'spring.root': Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46'] System.Configuration.BaseConfigurationRecord.EvaluateOne(String[] keys, SectionInput input, Boolean isTrusted, FactoryRecord factoryRecord, SectionRecord sectionRecord, Object parentResult) +202 System.Configuration.BaseConfigurationRecord.Evaluate(FactoryRecord factoryRecord, SectionRecord sectionRecord, Object parentResult, Boolean getLkg, Boolean getRuntimeObject, Object& result, Object& resultRuntimeObject) +1061 System.Configuration.BaseConfigurationRecord.GetSectionRecursive(String configKey, Boolean getLkg, Boolean checkPermission, Boolean getRuntimeObject, Boolean requestIsHere, Object& result, Object& resultRuntimeObject) +1431 System.Configuration.BaseConfigurationRecord.GetSection(String configKey, Boolean getLkg, Boolean checkPermission) +56 System.Configuration.BaseConfigurationRecord.GetSection(String configKey) +8 System.Web.Configuration.HttpConfigurationSystem.GetApplicationSection(String sectionName) +45 System.Web.Configuration.HttpConfigurationSystem.GetSection(String sectionName) +49 System.Web.Configuration.HttpConfigurationSystem.System.Configuration.Internal.IInternalConfigSystem.GetSection(String configKey) +6 System.Configuration.ConfigurationManager.GetSection(String sectionName) +78 Spring.Util.ConfigurationUtils.GetSection(String sectionName) in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Util\ConfigurationUtils.cs:69 Spring.Context.Support.ContextRegistry.InitializeContextIfNeeded() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextRegistry.cs:340 Spring.Context.Support.ContextRegistry.GetContext() in l:\projects\spring-net\trunk\src\Spring\Spring.Core\Context\Support\ContextRegistry.cs:206 Spring.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(String reference, Uri[] baseAddresses) in l:\projects\spring-net\trunk\src\Spring\Spring.Services\ServiceModel\Activation\ServiceHostFactory.cs:66 System.ServiceModel.HostingManager.CreateService(String normalizedVirtualPath) +11687036 System.ServiceModel.HostingManager.ActivateService(String normalizedVirtualPath) +42 System.ServiceModel.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath) +479 [ServiceActivationException: The service '/HHGEstimating.svc' cannot be activated due to an exception during compilation. The exception message is: Error creating context 'spring.root': Error thrown by a dependency of object 'HHGEstimating' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46' : '1' constructor arguments specified but no matching constructor found in object 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' (hint: specify argument indexes, names, or types to avoid ambiguities). while resolving 'TypeAttributes[2]' to 'System.ServiceModel.ServiceKnownTypeAttribute#25A5628' defined in 'assembly [IGCSoftware.HHG.WebService, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null], resource [IGCSoftware.HHG.WebService.Resources.Spring.objects.xml] line 46'.] System.ServiceModel.AsyncResult.End(IAsyncResult result) +11592858 System.ServiceModel.Activation.HostedHttpRequestAsyncResult.End(IAsyncResult result) +194 System.ServiceModel.Activation.HostedHttpRequestAsyncResult.ExecuteSynchronous(HttpApplication context, Boolean flowContext) +176 System.ServiceModel.Activation.HttpModule.ProcessRequest(Object sender, EventArgs e) +275 System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +68 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75

  Read the article

• Accessing the calling object into ajax response... (not the ajax call)

  - by Nishchay Sharma

  I have an object of type Application (defined by me). Whenever an object of this type is created, it automatically loads a php file say "start.php" using jquery ajax and assign the response to a div say "Respo". Now what i want is to access the Application object from that Respo div. Unfortunately, i have no clue how to do this... in my ajax call: function Application(options) { ....... var appObj=this; $.ajax({ url:appObj.location, //Already defined success:function(data) { $("#respo").html(data); } }); } Now in my Respo division i want to access that Application object... I tried: alert(this) but it resulted in an object of DOMWindow... i tried editing success function as: function Application(options) { ....... var appObj=this; $.ajax({ url:appObj.location, //Already defined success:function(data) { $("#respo").html("<script type='text/javascript'>var Self="+appObj+"</script>"); $("#respo").html(data); } }); } But i ended nowhere. :( Although if i assign "var Self='nishchay';" then alerting Self from start.php gives nishchay but i am not able to assign the calling object of Application type to the Self variable. It is the only way I cud think of. :\ Please help me... actually my object has some editing functions to control itself - its look and feel and some other options. I want the code loaded by object to control the object itself. Please help me.. Thanks in advance. Nishchay

  Read the article

• How can I get size in bytes of an object sent using RMI?

  - by Lucas Batistussi

  I'm implementing a cache server with MongoDB and ConcurrentHashMap java class. When there are available space to put object in memory, it will put at. Otherwise, the object will be saved in a mongodb database. Is allowed that user specify a size limit in memory (this should not exceed heap size limit obviously!) for the memory cache. The clients can use the cache service connecting through RMI. I need to know the size of each object to verify if a new incoming object can be put into memory. I searched over internet and i got this solution to get size: public long getObjectSize(Object o){ try { ByteArrayOutputStream bos = new ByteArrayOutputStream(); ObjectOutputStream oos = new ObjectOutputStream(bos); oos.writeObject(o); oos.close(); return bos.size(); } catch (Exception e) { return Long.MAX_VALUE; } } This solution works very well. But, in terms of memory use doesn't solve my problem. :( If many clients are verifying the object size at same time this will cause stack overflow, right? Well... some people can say: Why you don't get the specific object size and store it in memory and when another object is need to put in memory check the object size? This is not possible because the objects are variable in size. :( Someone can help me? I was thinking in get socket from RMI communication, but I don't know how to do this...

  Read the article

• Metro: Creating an IndexedDbDataSource for WinJS

  - by Stephen.Walther

  The goal of this blog entry is to describe how you can create custom data sources which you can use with the controls in the WinJS library. In particular, I explain how you can create an IndexedDbDataSource which you can use to store and retrieve data from an IndexedDB database. If you want to skip ahead, and ignore all of the fascinating content in-between, I’ve included the complete code for the IndexedDbDataSource at the very bottom of this blog entry. What is IndexedDB? IndexedDB is a database in the browser. You can use the IndexedDB API with all modern browsers including Firefox, Chrome, and Internet Explorer 10. And, of course, you can use IndexedDB with Metro style apps written with JavaScript. If you need to persist data in a Metro style app written with JavaScript then IndexedDB is a good option. Each Metro app can only interact with its own IndexedDB databases. And, IndexedDB provides you with transactions, indices, and cursors – the elements of any modern database. An IndexedDB database might be different than the type of database that you normally use. An IndexedDB database is an object-oriented database and not a relational database. Instead of storing data in tables, you store data in object stores. You store JavaScript objects in an IndexedDB object store. You create new IndexedDB object stores by handling the upgradeneeded event when you attempt to open a connection to an IndexedDB database. For example, here’s how you would both open a connection to an existing database named TasksDB and create the TasksDB database when it does not already exist: var reqOpen = window.indexedDB.open(“TasksDB”, 2); reqOpen.onupgradeneeded = function (evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); }; reqOpen.onsuccess = function () { var db = reqOpen.result; // Do something with db }; When you call window.indexedDB.open(), and the database does not already exist, then the upgradeneeded event is raised. In the code above, the upgradeneeded handler creates a new object store named tasks. The new object store has an auto-increment column named id which acts as the primary key column. If the database already exists with the right version, and you call window.indexedDB.open(), then the success event is raised. At that point, you have an open connection to the existing database and you can start doing something with the database. You use asynchronous methods to interact with an IndexedDB database. For example, the following code illustrates how you would add a new object to the tasks object store: var transaction = db.transaction(“tasks”, “readwrite”); var reqAdd = transaction.objectStore(“tasks”).add({ name: “Feed the dog” }); reqAdd.onsuccess = function() { // Tasks added successfully }; The code above creates a new database transaction, adds a new task to the tasks object store, and handles the success event. If the new task gets added successfully then the success event is raised. Creating a WinJS IndexedDbDataSource The most powerful control in the WinJS library is the ListView control. This is the control that you use to display a collection of items. If you want to display data with a ListView control, you need to bind the control to a data source. The WinJS library includes two objects which you can use as a data source: the List object and the StorageDataSource object. The List object enables you to represent a JavaScript array as a data source and the StorageDataSource enables you to represent the file system as a data source. If you want to bind an IndexedDB database to a ListView then you have a choice. You can either dump the items from the IndexedDB database into a List object or you can create a custom data source. I explored the first approach in a previous blog entry. In this blog entry, I explain how you can create a custom IndexedDB data source. Implementing the IListDataSource Interface You create a custom data source by implementing the IListDataSource interface. This interface contains the contract for the methods which the ListView needs to interact with a data source. The easiest way to implement the IListDataSource interface is to derive a new object from the base VirtualizedDataSource object. The VirtualizedDataSource object requires a data adapter which implements the IListDataAdapter interface. Yes, because of the number of objects involved, this is a little confusing. Your code ends up looking something like this: var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); The code above is used to create a new class named IndexedDbDataSource which derives from the base VirtualizedDataSource class. In the constructor for the new class, the base class _baseDataSourceConstructor() method is called. A data adapter is passed to the _baseDataSourceConstructor() method. The code above creates a new method exposed by the IndexedDbDataSource named nuke(). The nuke() method deletes all of the objects from an object store. The code above also overrides a method named remove(). Our derived remove() method accepts any type of key and removes the matching item from the object store. Almost all of the work of creating a custom data source goes into building the data adapter class. The data adapter class implements the IListDataAdapter interface which contains the following methods: · change() · getCount() · insertAfter() · insertAtEnd() · insertAtStart() · insertBefore() · itemsFromDescription() · itemsFromEnd() · itemsFromIndex() · itemsFromKey() · itemsFromStart() · itemSignature() · moveAfter() · moveBefore() · moveToEnd() · moveToStart() · remove() · setNotificationHandler() · compareByIdentity Fortunately, you are not required to implement all of these methods. You only need to implement the methods that you actually need. In the case of the IndexedDbDataSource, I implemented the getCount(), itemsFromIndex(), insertAtEnd(), and remove() methods. If you are creating a read-only data source then you really only need to implement the getCount() and itemsFromIndex() methods. Implementing the getCount() Method The getCount() method returns the total number of items from the data source. So, if you are storing 10,000 items in an object store then this method would return the value 10,000. Here’s how I implemented the getCount() method: getCount: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore().then(function (store) { var reqCount = store.count(); reqCount.onerror = that._error; reqCount.onsuccess = function (evt) { complete(evt.target.result); }; }); }); } The first thing that you should notice is that the getCount() method returns a WinJS promise. This is a requirement. The getCount() method is asynchronous which is a good thing because all of the IndexedDB methods (at least the methods implemented in current browsers) are also asynchronous. The code above retrieves an object store and then uses the IndexedDB count() method to get a count of the items in the object store. The value is returned from the promise by calling complete(). Implementing the itemsFromIndex method When a ListView displays its items, it calls the itemsFromIndex() method. By default, it calls this method multiple times to get different ranges of items. Three parameters are passed to the itemsFromIndex() method: the requestIndex, countBefore, and countAfter parameters. The requestIndex indicates the index of the item from the database to show. The countBefore and countAfter parameters represent hints. These are integer values which represent the number of items before and after the requestIndex to retrieve. Again, these are only hints and you can return as many items before and after the request index as you please. Here’s how I implemented the itemsFromIndex method: itemsFromIndex: function (requestIndex, countBefore, countAfter) { var that = this; return new WinJS.Promise(function (complete, error) { that.getCount().then(function (count) { if (requestIndex >= count) { return WinJS.Promise.wrapError(new WinJS.ErrorFromName(WinJS.UI.FetchError.doesNotExist)); } var startIndex = Math.max(0, requestIndex - countBefore); var endIndex = Math.min(count, requestIndex + countAfter + 1); that._getObjectStore().then(function (store) { var index = 0; var items = []; var req = store.openCursor(); req.onerror = that._error; req.onsuccess = function (evt) { var cursor = evt.target.result; if (index < startIndex) { index = startIndex; cursor.advance(startIndex); return; } if (cursor && index < endIndex) { index++; items.push({ key: cursor.value[store.keyPath].toString(), data: cursor.value }); cursor.continue(); return; } results = { items: items, offset: requestIndex - startIndex, totalCount: count }; complete(results); }; }); }); }); } In the code above, a cursor is used to iterate through the objects in an object store. You fetch the next item in the cursor by calling either the cursor.continue() or cursor.advance() method. The continue() method moves forward by one object and the advance() method moves forward a specified number of objects. Each time you call continue() or advance(), the success event is raised again. If the cursor is null then you know that you have reached the end of the cursor and you can return the results. Some things to be careful about here. First, the return value from the itemsFromIndex() method must implement the IFetchResult interface. In particular, you must return an object which has an items, offset, and totalCount property. Second, each item in the items array must implement the IListItem interface. Each item should have a key and a data property. Implementing the insertAtEnd() Method When creating the IndexedDbDataSource, I wanted to go beyond creating a simple read-only data source and support inserting and deleting objects. If you want to support adding new items with your data source then you need to implement the insertAtEnd() method. Here’s how I implemented the insertAtEnd() method for the IndexedDbDataSource: insertAtEnd:function(unused, data) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function(store) { var reqAdd = store.add(data); reqAdd.onerror = that._error; reqAdd.onsuccess = function (evt) { var reqGet = store.get(evt.target.result); reqGet.onerror = that._error; reqGet.onsuccess = function (evt) { var newItem = { key:evt.target.result[store.keyPath].toString(), data:evt.target.result } complete(newItem); }; }; }); }); } When implementing the insertAtEnd() method, you need to be careful to return an object which implements the IItem interface. In particular, you should return an object that has a key and a data property. The key must be a string and it uniquely represents the new item added to the data source. The value of the data property represents the new item itself. Implementing the remove() Method Finally, you use the remove() method to remove an item from the data source. You call the remove() method with the key of the item which you want to remove. Implementing the remove() method in the case of the IndexedDbDataSource was a little tricky. The problem is that an IndexedDB object store uses an integer key and the VirtualizedDataSource requires a string key. For that reason, I needed to override the remove() method in the derived IndexedDbDataSource class like this: var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); When you call remove(), you end up calling a method of the IndexedDbDataAdapter named removeInternal() . Here’s what the removeInternal() method looks like: setNotificationHandler: function (notificationHandler) { this._notificationHandler = notificationHandler; }, removeInternal: function(key) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqDelete = store.delete (key); reqDelete.onerror = that._error; reqDelete.onsuccess = function (evt) { that._notificationHandler.removed(key.toString()); complete(); }; }); }); } The removeInternal() method calls the IndexedDB delete() method to delete an item from the object store. If the item is deleted successfully then the _notificationHandler.remove() method is called. Because we are not implementing the standard IListDataAdapter remove() method, we need to notify the data source (and the ListView control bound to the data source) that an item has been removed. The way that you notify the data source is by calling the _notificationHandler.remove() method. Notice that we get the _notificationHandler in the code above by implementing another method in the IListDataAdapter interface: the setNotificationHandler() method. You can raise the following types of notifications using the _notificationHandler: · beginNotifications() · changed() · endNotifications() · inserted() · invalidateAll() · moved() · removed() · reload() These methods are all part of the IListDataNotificationHandler interface in the WinJS library. Implementing the nuke() Method I wanted to implement a method which would remove all of the items from an object store. Therefore, I created a method named nuke() which calls the IndexedDB clear() method: nuke: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqClear = store.clear(); reqClear.onerror = that._error; reqClear.onsuccess = function (evt) { that._notificationHandler.reload(); complete(); }; }); }); } Notice that the nuke() method calls the _notificationHandler.reload() method to notify the ListView to reload all of the items from its data source. Because we are implementing a custom method here, we need to use the _notificationHandler to send an update. Using the IndexedDbDataSource To illustrate how you can use the IndexedDbDataSource, I created a simple task list app. You can add new tasks, delete existing tasks, and nuke all of the tasks. You delete an item by selecting an item (swipe or right-click) and clicking the Delete button. Here’s the HTML page which contains the ListView, the form for adding new tasks, and the buttons for deleting and nuking tasks: <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title>DataSources</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.1.0.RC/css/ui-dark.css" rel="stylesheet" /> <script src="//Microsoft.WinJS.1.0.RC/js/base.js"></script> <script src="//Microsoft.WinJS.1.0.RC/js/ui.js"></script> <!-- DataSources references --> <link href="indexedDb.css" rel="stylesheet" /> <script type="text/javascript" src="indexedDbDataSource.js"></script> <script src="indexedDb.js"></script> </head> <body> <div id="tmplTask" data-win-control="WinJS.Binding.Template"> <div class="taskItem"> Id: <span data-win-bind="innerText:id"></span> <br /><br /> Name: <span data-win-bind="innerText:name"></span> </div> </div> <div id="lvTasks" data-win-control="WinJS.UI.ListView" data-win-options="{ itemTemplate: select('#tmplTask'), selectionMode: 'single' }"></div> <form id="frmAdd"> <fieldset> <legend>Add Task</legend> <label>New Task</label> <input id="inputTaskName" required /> <button>Add</button> </fieldset> </form> <button id="btnNuke">Nuke</button> <button id="btnDelete">Delete</button> </body> </html> And here is the JavaScript code for the TaskList app: /// <reference path="//Microsoft.WinJS.1.0.RC/js/base.js" /> /// <reference path="//Microsoft.WinJS.1.0.RC/js/ui.js" /> function init() { WinJS.UI.processAll().done(function () { var lvTasks = document.getElementById("lvTasks").winControl; // Bind the ListView to its data source var tasksDataSource = new DataSources.IndexedDbDataSource("TasksDB", 1, "tasks", upgrade); lvTasks.itemDataSource = tasksDataSource; // Wire-up Add, Delete, Nuke buttons document.getElementById("frmAdd").addEventListener("submit", function (evt) { evt.preventDefault(); tasksDataSource.beginEdits(); tasksDataSource.insertAtEnd(null, { name: document.getElementById("inputTaskName").value }).done(function (newItem) { tasksDataSource.endEdits(); document.getElementById("frmAdd").reset(); lvTasks.ensureVisible(newItem.index); }); }); document.getElementById("btnDelete").addEventListener("click", function () { if (lvTasks.selection.count() == 1) { lvTasks.selection.getItems().done(function (items) { tasksDataSource.remove(items[0].data.id); }); } }); document.getElementById("btnNuke").addEventListener("click", function () { tasksDataSource.nuke(); }); // This method is called to initialize the IndexedDb database function upgrade(evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); } }); } document.addEventListener("DOMContentLoaded", init); The IndexedDbDataSource is created and bound to the ListView control with the following two lines of code: var tasksDataSource = new DataSources.IndexedDbDataSource("TasksDB", 1, "tasks", upgrade); lvTasks.itemDataSource = tasksDataSource; The IndexedDbDataSource is created with four parameters: the name of the database to create, the version of the database to create, the name of the object store to create, and a function which contains code to initialize the new database. The upgrade function creates a new object store named tasks with an auto-increment property named id: function upgrade(evt) { var newDB = evt.target.result; newDB.createObjectStore("tasks", { keyPath: "id", autoIncrement: true }); } The Complete Code for the IndexedDbDataSource Here’s the complete code for the IndexedDbDataSource: (function () { /************************************************ * The IndexedDBDataAdapter enables you to work * with a HTML5 IndexedDB database. *************************************************/ var IndexedDbDataAdapter = WinJS.Class.define( function (dbName, dbVersion, objectStoreName, upgrade, error) { this._dbName = dbName; // database name this._dbVersion = dbVersion; // database version this._objectStoreName = objectStoreName; // object store name this._upgrade = upgrade; // database upgrade script this._error = error || function (evt) { console.log(evt.message); }; }, { /******************************************* * IListDataAdapter Interface Methods ********************************************/ getCount: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore().then(function (store) { var reqCount = store.count(); reqCount.onerror = that._error; reqCount.onsuccess = function (evt) { complete(evt.target.result); }; }); }); }, itemsFromIndex: function (requestIndex, countBefore, countAfter) { var that = this; return new WinJS.Promise(function (complete, error) { that.getCount().then(function (count) { if (requestIndex >= count) { return WinJS.Promise.wrapError(new WinJS.ErrorFromName(WinJS.UI.FetchError.doesNotExist)); } var startIndex = Math.max(0, requestIndex - countBefore); var endIndex = Math.min(count, requestIndex + countAfter + 1); that._getObjectStore().then(function (store) { var index = 0; var items = []; var req = store.openCursor(); req.onerror = that._error; req.onsuccess = function (evt) { var cursor = evt.target.result; if (index < startIndex) { index = startIndex; cursor.advance(startIndex); return; } if (cursor && index < endIndex) { index++; items.push({ key: cursor.value[store.keyPath].toString(), data: cursor.value }); cursor.continue(); return; } results = { items: items, offset: requestIndex - startIndex, totalCount: count }; complete(results); }; }); }); }); }, insertAtEnd:function(unused, data) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function(store) { var reqAdd = store.add(data); reqAdd.onerror = that._error; reqAdd.onsuccess = function (evt) { var reqGet = store.get(evt.target.result); reqGet.onerror = that._error; reqGet.onsuccess = function (evt) { var newItem = { key:evt.target.result[store.keyPath].toString(), data:evt.target.result } complete(newItem); }; }; }); }); }, setNotificationHandler: function (notificationHandler) { this._notificationHandler = notificationHandler; }, /***************************************** * IndexedDbDataSource Method ******************************************/ removeInternal: function(key) { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqDelete = store.delete (key); reqDelete.onerror = that._error; reqDelete.onsuccess = function (evt) { that._notificationHandler.removed(key.toString()); complete(); }; }); }); }, nuke: function () { var that = this; return new WinJS.Promise(function (complete, error) { that._getObjectStore("readwrite").done(function (store) { var reqClear = store.clear(); reqClear.onerror = that._error; reqClear.onsuccess = function (evt) { that._notificationHandler.reload(); complete(); }; }); }); }, /******************************************* * Private Methods ********************************************/ _ensureDbOpen: function () { var that = this; // Try to get cached Db if (that._cachedDb) { return WinJS.Promise.wrap(that._cachedDb); } // Otherwise, open the database return new WinJS.Promise(function (complete, error, progress) { var reqOpen = window.indexedDB.open(that._dbName, that._dbVersion); reqOpen.onerror = function (evt) { error(); }; reqOpen.onupgradeneeded = function (evt) { that._upgrade(evt); that._notificationHandler.invalidateAll(); }; reqOpen.onsuccess = function () { that._cachedDb = reqOpen.result; complete(that._cachedDb); }; }); }, _getObjectStore: function (type) { type = type || "readonly"; var that = this; return new WinJS.Promise(function (complete, error) { that._ensureDbOpen().then(function (db) { var transaction = db.transaction(that._objectStoreName, type); complete(transaction.objectStore(that._objectStoreName)); }); }); }, _get: function (key) { return new WinJS.Promise(function (complete, error) { that._getObjectStore().done(function (store) { var reqGet = store.get(key); reqGet.onerror = that._error; reqGet.onsuccess = function (item) { complete(item); }; }); }); } } ); var IndexedDbDataSource = WinJS.Class.derive( WinJS.UI.VirtualizedDataSource, function (dbName, dbVersion, objectStoreName, upgrade, error) { this._adapter = new IndexedDbDataAdapter(dbName, dbVersion, objectStoreName, upgrade, error); this._baseDataSourceConstructor(this._adapter); }, { nuke: function () { this._adapter.nuke(); }, remove: function (key) { this._adapter.removeInternal(key); } } ); WinJS.Namespace.define("DataSources", { IndexedDbDataSource: IndexedDbDataSource }); })(); Summary In this blog post, I provided an overview of how you can create a new data source which you can use with the WinJS library. I described how you can create an IndexedDbDataSource which you can use to bind a ListView control to an IndexedDB database. While describing how you can create a custom data source, I explained how you can implement the IListDataAdapter interface. You also learned how to raise notifications — such as a removed or invalidateAll notification — by taking advantage of the methods of the IListDataNotificationHandler interface.

  Read the article

• Json.Net Issues: StackOverflowException is thrown when serialising circular dependent ISerializable object with ReferenceLoopHandling.Ignore

  - by keyr

  I have a legacy application that used binary serialisation to persist the data. Now we wanted to use Json.net 4.5 to serialise the data without much changes to the existing classes. Things were working nice till we hit a circular dependent class. Is there any workaround to solve this problem? Sample code as shown below [Serializable] class Department : ISerializable { public Employee Manager { get; set; } public string Name { get; set; } public Department() { } public Department( SerializationInfo info, StreamingContext context ) { Manager = ( Employee )info.GetValue( "Manager", typeof( Employee ) ); Name = ( string )info.GetValue( "Name", typeof( string ) ); } public void GetObjectData( SerializationInfo info, StreamingContext context ) { info.AddValue( "Manager", Manager ); info.AddValue( "Name", Name ); } } [Serializable] class Employee : ISerializable { [NonSerialized] //This does not work [XmlIgnore]//This does not work private Department mDepartment; public Department Department { get { return mDepartment; } set { mDepartment = value; } } public string Name { get; set; } public Employee() { } public Employee( SerializationInfo info, StreamingContext context ) { Department = ( Department )info.GetValue( "Department", typeof( Department ) ); Name = ( string )info.GetValue( "Name", typeof( string ) ); } public void GetObjectData( SerializationInfo info, StreamingContext context ) { info.AddValue( "Department", Department ); info.AddValue( "Name", Name ); } } And the test code Department department = new Department(); department.Name = "Dept1"; Employee emp1 = new Employee { Name = "Emp1", Department = department }; department.Manager = emp1; Employee emp2 = new Employee() { Name = "Emp2", Department = department }; IList<Employee> employees = new List<Employee>(); employees.Add( emp1 ); employees.Add( emp2 ); var memoryStream = new MemoryStream(); var formatter = new BinaryFormatter(); formatter.Serialize( memoryStream, employees ); memoryStream.Seek( 0, SeekOrigin.Begin ); IList<Employee> deserialisedEmployees = formatter.Deserialize( memoryStream ) as IList<Employee>; //Works nicely JsonSerializerSettings jsonSS= new JsonSerializerSettings(); jsonSS.TypeNameHandling = TypeNameHandling.Objects; jsonSS.TypeNameAssemblyFormat = FormatterAssemblyStyle.Full; jsonSS.Formatting = Formatting.Indented; jsonSS.ReferenceLoopHandling = ReferenceLoopHandling.Ignore; //This is not working!! //jsonSS.ReferenceLoopHandling = ReferenceLoopHandling.Serialize; //This is also not working!! jsonSS.PreserveReferencesHandling = PreserveReferencesHandling.All; string jsonAll = JsonConvert.SerializeObject( employees, jsonSS ); //Throws stackoverflow exception Edit1: The issue has been reported to Json (http://json.codeplex.com/workitem/23668)

  Read the article

• Visual Studio Code Analysis: CA0001 Error Running Code Analysis - object reference not set to an instance of an object

  - by sturdytree

  For a WPF application being developed in VS 2012 (Ultimate), the application runs fine when a particular project's code analysis is disabled. Enabling it results in the error above. This was working fine until recently (i.e. running with code analysis enabled for the particular project) and the only recent change I can think of is removing NHibernate Profiler (using NuGet). Will be grateful for any pointers on how to debug this, or to see a more detailed log/error message.

  Read the article

• Listview of items from a object selected in another listview

  - by Ingó Vals

  Ok the title maybe a little confusing. I have a database with the table Companies wich has one-to-many relotionship with another table Divisions ( so each company can have many divisions ) and division will have many employees. I have a ListView of the companies. What I wan't is that when I choose a company from the ListView another ListView of divisions within that company appears below it. Then I pick a division and another listview of employees within that division appaers below that. You get the picture. Is there anyway to do this mostly inside the XAML code declaritively (sp?). I'm using linq so the Company entity objects have a property named Division wich if I understand linq correctly should include Division objects of the divisions connected to the company. So after getting all the companies and putting them as a itemsource to CompanyListView this is where I currently am. <ListView x:Name="CompanyListView" DisplayMemberPath="CompanyName" Grid.Row="0" Grid.Column="0" /> <ListView DataContext="{Binding ElementName=CompanyListView, Path=SelectedItem}" DisplayMemberPath="Division.DivisionName" Grid.Row="1" Grid.Column="0" /> I know I'm way off but I was hoping by putting something specific in the DataContext and DisplayMemberPath I could get this to work. If not then I have to capture the Id of the company I guess and capture a select event or something. Another issue but related is the in the seconde column besides the lisview I wan't to have a details/edit view for the selected item. So when only a company is selected details about that will appear then when a division under the company is picked It will go there instead, any ideas?

  Read the article

• Enum in WCF RIA Services Object

  - by Blake Blackwell

  Is it possible to have an enum with WCF RIA Services? When I check the generated code for my custom POCO class I don't see the enum property generated. Here is an example of what I'm trying to do: public class Legend { public enum ViewStateType { OnExpanded = 1, OnContracted = 2, OffExpanded = 3, OffContracted = 4 } [Key] public Guid LegendId { get; set; } [EnumDataType(typeof(ViewStateType))] public ViewStateType ViewState { get; set; } } I tried with and without the EnumDataType attribute.

  Read the article

• iPhone: How to write plist array of dictionary object

  - by Alessandro

  Hello, I'm a young Italian developer for the iPhone. I have a plist file (named "Frase") with this structure: Root Array - Item 0 Dictionary Frase String Preferito Bool - Item 1 Dictionary Frase String Preferito Bool - Item 2 Dictionary Frase String Preferito Bool - Item 3 Dictionary Frase String Preferito Bool exc. An array that contains many elements dictionary, all the same, consisting of "Frase" (string) and "Preferito" (BOOL). The variable "indirizzo", increase or decrease the click of the button Next or Back. The application interface: http://img691.imageshack.us/img691/357/schermata20100418a20331.png When I click on AddPreferito button, the item "Preferito" must be YES. Subsequently, the array must be updated with the new dictionary.The code: (void)addpreferito:(id)sender { NSString *plistPath = [[NSBundle mainBundle] pathForResource:@"Frase" ofType:@"plist"]; MSMutableArray *frase = [[NSMutableArray alloc] initWithContentsOfFile:plistPath]; NSMutableDictionary *dictionary = [frase objectAtIndex:indirizzo]; [dictionary setValue: YES forKey:@"Preferito"]; [frase replaceObjectAtIndex:indirizzo withObject:dictionary]; [frase writeToFile:plistPath atomically:YES]; } Why not work? Thanks Thanks Thanks!

  Read the article

• Hierarchical templating multiple object types in silverlight

  - by Dan Wray

  Is it possible and if so what is the best way to implement the following hierarchical structure in a silverlight (4) TreeView control? (where Item and Group are classes which can exist in the tree). Group | |-Item | |-Group | | | |-Item | | | |-Item | |-Item The structure could of course be arbitrarily more complex than this, if needed. HierarchicalDataTemplates appear to be the way to approach this, but I'm specifically having trouble understanding how I might apply the template to interpret the different classes correctly. A similar question was asked for WPF, the answer for which made use of the TargetType property on the HierarchicalDataTemplate, but I am uncertain whether that property is available in the silverlight version since I don't appear to have access to it in my environment.

  Read the article

< Previous Page | 199 200 201 202 203 204 205 206 207 208 209 210  | Next Page >