Visual Basic 2005 has many new and improved language features -- such as inheritance, interfaces, overriding, shared members, and overloading -- that make it a powerful object-oriented programming language. As a Visual Basic developer, you can now create multithreaded, scalable applications using explicit multithreading. This language has following new features,
Continue Statement, which immediately skips to the next iteration of a Do, For, or While loop.
IsNot operator, which you can avoid using the Not and Is operators in an awkward order.
- 3.
Using... End. Using statement block ensures disposal of a system resource when your code leaves the block for any reason.
4. Public Sub setbigbold( _
5. ByVal c As Control)
6. Using nf As New _
7. System.Drawing.Font("Arial",_
8. 12.0F, FontStyle.Bold)
9. c.Font = nf
10. c.Text = "This is" &_
11. "12-point Arial bold"
12.End Using
End Sub
- Explicit Zero Lower Bound on an Array, Visual Basic now permits an array declaration to specify the lower bound (0) of each dimension along with the upper bound.
- Unsigned Types, Visual Basic now supports unsigned integer data types (
UShort , UInteger , and ULong ) as well as the signed type SByte .
- Operator Overloading, Visual Basic now allows you to define a standard operator (such as
+ , & , Not, or Mod) on a class or structure you have defined.
- Partial Types, to separate generated code from your authored code into separate source files.
- Visual Basic now supports type parameters on generic classes, structures, interfaces, procedures, and delegates. A corresponding type argument specifies at compilation time the data type of one of the elements in the generic type.
- Custom Events. You can declare custom events by using the Custom keyword as a modifier for the Event statement. In a custom event, you specify exactly what happens when code adds or removes an event handler to or from the event, or when code raises the event.
- Compiler Checking Options, The /nowarn and /warnaserror options provide more control over how warnings are handled. Each one of these compiler options now takes a list of warning IDs as an optional parameter, to specify to which warnings the option applies.
- There are eight new command-line compiler options:
- The /codepage option specifies which codepage to use when opening source files.
- The /doc option generates an XML documentation file based on comments within your code.
- The /errorreport option provides a convenient way to report a Visual Basic internal compiler error to Microsoft.
- The /filealign option specifies the size of sections in your output file.
- The /noconfig option causes the compiler to ignore the Vbc.rsp file.
- The /nostdlib option prevents the import of mscorlib.dll, which defines the entire System namespace.
- The /platform option specifies the processor to be targeted by the output file, in those situations where it is necessary to explicitly specify it.
- The /unify option suppresses warnings resulting from a mismatch between the versions of directly and indirectly referenced assemblies.
| With the release of Visual Studio 2005, the C# language has been updated to version 2.0. This language has following new features:
- Generics types are added to the language to enable programmers to achieve a high level of code reuse and enhanced performance for collection classes. Generic types can differ only by arity. Parameters can also be forced to be specific types.
- Iterators make it easier to dictate how a for each loop will iterate over a collection's contents.
3.
4. public class NumChar
5. {
6. string[] saNum = {
7. "One", "Two", "Three",
8. "Four", "Five", "Six",
9. "Seven", "Eight", "Nine",
10. "Zero"};
11.public
12. System.Collections.IEnumerator
13. GetEnumerator()
14.{
15.foreach (string num in saNum)
16.yield return num;
17.}
18.}
19.
20.
21.NumChar oNumChar = new NumChar();
22.
23.foreach (string num in oNumChar)
24.Console.WriteLine(num);
Partial type definitions allow a single type, such as a class, to be split into multiple files. The Visual Studio designer uses this feature to separate its generated code from user code.
Nullable types allow a variable to contain a value that is undefined.
Anonymous Method is now possible to pass a block of code as a parameter. Anywhere a delegate is expected, a code block can be used instead: There is no need to define a new method.
28.button1.Click +=
29. delegate { MessageBox.Show(
"Click!") };
- . The namespace alias qualifier (
:: ) provides more control over accessing namespace members. The global :: alias allows to access the root namespace that may be hidden by an entity in your code.
Static classes are a safe and convenient way of declaring a class containing static methods that cannot be instantiated. In C# v1.2 you would have defined the class constructor as private to prevent the class being instantiated.
- 8. There are eight new compiler options:
- /langversion option: Can be used to specify compatibility with a specific version of the language.
- /platform option: Enables you to target IPF (IA64 or Itanium) and AMD64 architectures.
- #pragma warning: Used to disable and enable individual warnings in code.
- /linkresource option: Contains additional options.
- /errorreport option: Can be used to report internal compiler errors to Microsoft over the Internet.
- /keycontainer and /keyfile: Support specifying cryptographic keys.
|
No comments:
Post a Comment