The topics in this part are listed below. The code snippets if any are based on the new C++ .NET syntaxes. The code snippets if any are based on the new C++ .NET syntaxes.
The Collections Namespaces
System::Collections is implemented in mscorlib.dll, while System::Collections::Specialized is implemented in system.dll, so if you want to use both, you’ll have to use two #using statements like the following:
#using <mscorlib.dll> // Can be excluded, available/included by default in VC++ 2005
#using <system.dll>
The following table lists the main classes that you’ll find in the System::Collections namespace.
| Class | Description |
| ArrayList | A dynamically growable array |
| BitArray | A class that stores a number of Boolean values as the individual bits of an integer |
| Hashtable | A hash table that stores objects by hash key |
| Queue | A list where objects are added at one end and retrieved from the other end |
| SortedList | A linked list whose members are maintained in sorted order |
| Stack | A first-in, last-out stack |
|
Table 8 | |
The following table shows the main classes and structures that you’ll find in the System::Collections::Specialized namespace. The System::Collections::Specialized namespace contains specialized and strongly-typed collections; for example, a linked list dictionary, a bit vector, and collections that contain only strings.
| Class | Description |
| BitVector32 | A class that stores a number of Boolean values as the individual bits of a 32-bit integer. |
| ListDictionary | A dictionary implemented using a singly linked list. |
| NameValueCollection | A sorted collection of string keys and values. |
| StringCollection | An unsorted collection of strings. |
| StringDictionary | A hash table with the key strongly typed to be a string rather than an object. |
| StringEnumerator | An enumerator to work with StringCollection. |
|
Table 9 | |
The System::Collections namespace also defines a series of interfaces that are used to define the behavior of the collection classes. The collection classes themselves implement one or more of these interfaces, and you can use them as the basis for writing your own collection classes. The main interfaces are listed in the following table.
| Interface | Description |
| ICollection | Defines the size, enumerator, and synchronization methods for all collections. |
| Icomparer | Defines a method for comparing two objects. |
| Idictionary | Implemented by collections that manage key/value pairs, such as Hashtable and ListDictionary. |
| IdictionaryEnumerator | Defines methods for enumerating over the items in a dictionary |
| Ienumerable | Defines the GetEnumerator method, which returns an Ienumerator; implemented by almost all collections. |
| Ienumerator | Defines the properties and methods of enumerators. |
| IhashCodeProvider | Implemented by classes that provide hash code values. |
| Ilist | Implemented by classes that define indexed collections of objects. |
|
Table 10 | |
In the .NET Framework version 2.0 there is new System::Collections::Generic namespace. The System::Collections::Generic namespace contains interfaces and classes that define generic collections, which allow users to create strongly typed collections that provide better type safety and performance than non-generic strongly typed collections. For more detail, check your .Net documentation for this thing.
The Diagnostics Namespace
System::Diagnostics provides a number of classes to:
Trace program execution.
Interact with the debugger.
Use the system event log.
Start system processes.
Monitor system performance.
All the classes in System::Diagnostics are implemented in system.dll.
The IO Namespace
The System::IO namespace, defined in mscorlib.dll, provides the classes that implement the .NET input/output (I/O) functionality. The main classes in this namespace are described in the following table.
| Class | Description |
| BinaryReader | Reads .NET primitive types from a byte stream. |
| BinaryWriter | Writes .NET primitive types to a byte stream. |
| Directory | Contains static methods for operating on directories. |
| DirectoryInfo | Represents a path to a directory, and contains methods for operating on the directory path. |
| File | Contains static methods for operating on files. |
| FileInfo | Represents a path to a file, and contains methods for operating on the file path. |
| FileStream | Reads and writes to files using streams. |
| FileSystemInfo | The base class for FileInfo and DirectoryInfo. |
| FileSystemWatcher | Watches for changes in the file system and fires events when changes occur. |
| IOException | The exception thrown when I/O errors occur. |
| MemoryStream | Reads and writes streams of bytes to and from memory. |
| Path | Represents directory strings in a platform-independent way. |
| Stream | The abstract base for the stream classes. |
| StreamReader | Reads Unicode characters from a byte stream. |
| StreamWriter | Writes Unicode characters to a byte stream. |
| StringReader | Reads Unicode characters from a string. |
| StringWriter | Writes Unicode characters to a string. |
| TextReader | The base class for StreamReader and StringReader. |
| TextWriter | The base class for StreamWriter and StringWriter. |
|
Table 11 | |
As with all the .NET Framework class library classes, these classes are language- independent. They can be used alongside or in place of the C++ stream classes.