Get result in single column from two columns data in table

CREATE TABLE TestTable (Col1 INT, Col2 INT)
GO Continue reading


ADO.NET questions

DataReader  (connected architecture. Connected architecture was built on the classes connection, command, datareader and transaction. ) Continue reading

INotifyPropertyChanged- WPF

A very common and popular way to synchronize data between the model and the view in WPF is using DataBinding. The value of the model is transferred to the view once, when the binding is initialized. But for every subsequent change, the model must notify the binding to transfer the value again. This is done by implementing the INotifyPropertyChangedinterface on the model.

In the setter of every bound property there must be some code to raise the PropertyChanged event, passing the name of the modified property as a string. This has some disadvantages:

  • You cannot use Auto-properties
  • The property name is passed as a string. This brings ugly errors, when you forgot to change the string after a rename.
  • Every property needs extra code


RelativeSources in WPF bindings

The RelativeSource is a markup extension that is used in particular binding cases when we try to bind a property of a given object to another property of the object itself, when we try to bind a property of a object to another one of its relative parents, when binding a dependency property value to a piece of XAML in case of custom control development and finally in case of using a differential of a series of a bound data. All of those situations are expressed as relative source modes. I will expose all of those cases one by one. Continue reading

Attached property – WPF. Also diff b/w attached and Dependdency prop

An attached property is intended to be used as a type of global property that is settable on any object. Attached properties are a special form of dependency property.  They exist so that a child element can store a value associated with a property defined on an ancestor element.  This is commonly used in the interaction between elements and the WPF layout infrastructure,. Continue reading