.NET/ASP.NET/C#/VB.NET PDF Document SDK
In the STL-style loop nothing has changed, except that this time the items referenced by the iterator can be modified. This example used the Iterator name instead of iterator, which does not affect the result (they are synonyms). It is not only possible to iterate in one direction but for STL-style iterators it is also possible to use the -- operator as well as the ++ operator. For Java-style iterators, the methods next, previous, findNext, and findPrevious are available. When using next and previous, it is important to guard the code by using hasNext and hasPrevious to avoid undefined results.barcode font excel 2010 free download, excel barcode generator, excel 2d barcode font, active barcode in excel 2003, barcode check digit excel formula, excel 2013 barcode font download, barcode for excel 2016, excel formula barcode check digit, how create barcode in excel 2010, barcode font for excel download,
Perhaps the best known alternative is NHibernate. This is a .NET version of Hibernate, a popular Java ORM (Object Relational Mapper). NHibernate had already been around for a few years by the time the Entity Framework emerged (and its Java progenitor is considerably older). So in many respects it s a more mature and more fully featured ORM than the Entity Framework. On the other hand, NHibernate predates LINQ (and Java currently has nothing resembling LINQ), so at the time of this writing, its LINQ support is somewhat limited. Many other ORMs are available for .NET, some free and some commercial. They are too numerous to mention here, as a quick web search will confirm.
Most communication with databases happens over specialized, vendor-specific protocols Firewalls are usually configured not to let such protocols through, and with good reason: from a security perspective, making your database directly accessible on the Internet tends to look like a very bad idea Nonetheless, some people want to do this, and there are scenarios in which it s not the terrible idea it might first seem, particularly if you can exercise sufficient control over what gets exposed With WCF Data Services, you can present a relational data store over HTTP and XML or JSON You can be selective about what data you expose and to whom Moreover, the model you present doesn t necessarily have to be the same as your underlying database structure.
In fact, there doesn t have to be a database involved at all there s a provider model that enables you to present any data through this mechanism, as long as you can find a way to make it look like relational data You will normally use WCF Data Services in conjunction with the Entity Framework you can define the entities you d like to present over HTTP, and use the framework s mapping services to bridge between that and the underlying data store So we ll be looking at these services in more detail later in the chapter, once we ve finished exploring the Entity Framework The focus of WCF Data Services is different than for the other data access features we ve discussed so far it s mainly about presenting data on the network, where everything else has been about consuming data.
Atlas provides a data-binding structure that allows you to wire components to each other and to data sources to allow them to integrate. It supports such features as two-way data binding that allows data sources to be edited and transforming that allows you to apply basic business logic to the data upon binding to change it from one value to another. Figure 2-8 shows an example of a data-bound control in Atlas. This comes from an example in 5, where I discuss data binding in more detail. Within Atlas, you can attribute your web services with the [DataObjectMethod()] attribute, which allows you to specify whether the connection is a select, insert, update, or delete operation.
When you pick an iterator to use, always try to use constant iterators when possible because they Tip
However, there s also a client-side component that provides LINQ-based querying for such services While it s part of the WCF Data Services technology, it s optional you re not obliged to use it on the client And this client doesn t strictly require WCF Data Services on the server the client-side parts could be used against any service that exposes data in the same way..
Silverlight uses a seriously trimmed down version of the .NET Framework to keep its download size and install time tolerably small. It doesn t have much data access support. In fact, size is not the only reason it wouldn t normally make sense for a
Silverlight client application to attempt to connect directly to a database, because Silverlight is a client-side web technology and most system administrators work to ensure that their databases are not accessible via their native protocols over the Internet. Of course, a direct connection to a database server might be an option in an intranet scenario, but it s not supported. Silverlight offers LINQ, but neither the LINQ to SQL nor the LINQ to Entity Framework providers are available, because the underlying database access mechanisms that these providers use are missing. The only supported database access mechanism in Silverlight is the WCF Data Services client.