Difference between revisions of "LazUtils"

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== TDictionaryStringList ==
 
== TDictionaryStringList ==
  
This is an unsorted StringList with a fast lookup feature. Internally it uses a string map container to store the string again. It is then used for InserItem, Contains, IndexOf and Find methods. The extra container does not reserve too much memory because the strings are reference counted and not really copied. All Duplicates property values are fully supported, including dupIgnore and dupError, unlike in unsorted StringList.
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This is an unsorted TStringList with a fast lookup feature. Internally it uses a string map container to store the string again. It is then used for InserItem, Contains, IndexOf and Find methods. The extra container does not reserve excessive memory because the strings are reference-counted and not actually copied. TDictionaryStringList fully supports all Duplicates property values including dupIgnore and dupError. An unsorted TStringList lacks this support for some values of Duplicates.
  
This class is useful only when you must preserve the order in list, but also need to do fast lookups to see if a string exists, or must prevent duplicates.
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This class is particularly useful when you need to preserve the order in which strings have been inserted in a list at the same time as needing the ability to do fast lookups (to check if a string is already listed), when you need to prevent addition of duplicate strings.

Revision as of 15:24, 19 March 2013

TDictionaryStringList

This is an unsorted TStringList with a fast lookup feature. Internally it uses a string map container to store the string again. It is then used for InserItem, Contains, IndexOf and Find methods. The extra container does not reserve excessive memory because the strings are reference-counted and not actually copied. TDictionaryStringList fully supports all Duplicates property values including dupIgnore and dupError. An unsorted TStringList lacks this support for some values of Duplicates.

This class is particularly useful when you need to preserve the order in which strings have been inserted in a list at the same time as needing the ability to do fast lookups (to check if a string is already listed), when you need to prevent addition of duplicate strings.