C # considerations for selecting a collection class

Considerations for selecting a collection class

 

 

Be careful when selecting the system. Collections class. The incorrect type may restrict your use of the set.

Consider the following:

• Do you need a sequence list where elements are generally discarded after retrieving their values?

  • If necessary, consider using the queue class or queue <(of <(T>) generic class when you need first-in-first-out (FIFO) behavior. Consider using a stack class or a stack <(of <(T>)> generic class when you need a later, first-in-first-out (LIFO) behavior.

  • If not, consider using other collections.

• Do I need to access elements in some order, such as FIFO, lifo, or random access?

  • The queue class and the queue <(of <(T>)> wildcard class provide FIFO access.

  • Stack class and stack <(of <(T>)> generic class provide LIFO access.

  • Shortlist <(of <(T>) generic classes allow sequential access from the beginning to the end or from the end to the beginning.

  • Other sets provide random access.

• Do I need to access each element through indexes?

  • The arraylist, stringcollection, and list <(of <(T>)> generic classes provide access to elements through the zero-start index of an element.

  • Hashtable, sortedlist, listdictionary, stringdictionary, and dictionary <(of <(tkey, tvalue>) and sorteddictionary <(of <(tkey, tvalue>) generic classes provide access to elements through element keys.

  • Nameobjectcollectionbase and namevaluecollection classes and keyedcollection <(of <(tkey, titem>) and sortedlist <(of <(tkey, tvalue>) A generic class provides access to an element through its element index starting from scratch or through its element key.

• Will each element contain a combination of values, keys, and values, or a combination of keys and values?

  • One Value: any set of generic Interfaces Based on the ilist interface or ilist <(of <(T>)>.

  • One key and one value: Use any set of idictionary-based or idictionary <(of <(tkey, tvalue>) Generic interfaces.

  • A value with an embedded key: uses the keyedcollection <(of <(tkey, titem>)> generic class.

  • One key and multiple values: Use the namevaluecollection class.

• Do I need to sort elements in a different way than the input element method?

  • The hashtable class sorts elements by their hash code.

  • Sortedlist class and sorteddictionary <(of <(tkey, tvalue>) and sortedlist <(of <(tkey, tvalue>) generic classes are sorted by keys based on The Implementation of The icomparer interface and the icomparer <(of <(T>) interface.

  • Arraylist provides the sort method, which accepts the icomparer implementation as a parameter. Its corresponding generic class (list <(of <(T>) provides the sort method, which accepts icomparer <(of <(T>) the implementation of generic interfaces is used as parameters.

• Do you need quick search and retrieval of information?

  • For a small set (10 or fewer items), listdictionary is faster than hashtable. Dictionary <(of <(tkey, tvalue>) generic classes provide faster searches than sorteddictionary <(of <(tkey, tvalue>) generic classes.

• Do I need to accept only the string set?

  • Both stringcollection (based on ilist) and stringdictionary (based on idictionary) are located in the system. Collections. Specialized namespace.

  • In addition, by specifying the string class for the generic type parameter, you can use any generic set class in the system. Collections. Generic namespace as a strongly typed string set.