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Showing posts from October, 2008

IE shortcuts

Ctrl + F Brings up the Find dialog box F5 Refreshes the page Ctrl + N Opens a new browser window Alt + Home Takes you to your homepage Escape Stops loading the current page Ctrl + A Selects the entire page F1

Windows shortcut keys

F2 Select a file and press F2 to rename the file F3 In Windows Explorer and on Desktop, pressing F3 brings up the Find dialog box Alt + Enter Select a file and press Alt + Enter to bring up its Properties dialog box Alt + Space bar Inside a window, press Alt + Spacebar to bring up the system menu of that window Ctrl + Escape Brings up the wi

some OOPS concepts and examples

The class is the description of the object and the object in an instance of the class. For example the class of humans would describe us as having the attributes such as arms, hands, legs and heads; and methods such as talk, think, eat, and sit. However each of us would be an instance of that class, an object. If I can jump it’s because humans can jump, if I can laugh, it’s because humans can laugh. That is, the class defines the methods and attributes for each object belonging to that class. POLYMORPHISM : Polymorphism is the ability for objects to respond differently to the same message, depending upon what type of object they are. For example, members from each of the following classes; Spouse, YoungerBrother, TotalStranger or LawEnforcementOfficer, are likely to behave differently when the hug method is called upon them. Polymorphism becomes very useful when we have a group of related objects upon which we want to perform an operation, but those objects may need to react in differe

Use of Hashes.

Hashes are an advanced form of array. One of the limitations of an array is that the information contained within it can be difficult to get to. For example, imagine that you have a list of people and their ages. The hash solves this problem very neatly by allowing us to access that @ages array not by an index, but by a scalar key. For example to use age of different people we can use thier names as key to define a hash. %ages = ('Martin' => 28, 'Sharon' => 35, 'Rikke' => 29,); print "Rikke is $ages{Rikke} years old\n"; This will produce following result Rikke is 29 years old