Working with String Lists

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One of the most commonly used types of lists is a list of character strings. Examples include items in a combo box, lines in a memo, names of fonts, and names of rows and columns in a string grid. The RTL provides a common interface to any list of strings through an object called TStrings and its descendants such as TStringList and THashedStringList. TStringList implements the abstract properties and methods introduced by TStrings, and introduces properties, events, and methods to

  • Sort the strings in the list.
  • Prohibit duplicate strings in sorted lists.
  • Respond to changes in the contents of the list.

In addition to providing functionality for maintaining string lists, these objects allow easy interoperability; for example, you can edit the lines of a memo (which are a TStrings descendant) and then use these lines as items in a combo box (also a TStrings descendant).

A string-list property appears in the Object Inspector with TStrings in the Value column. Double-click TStrings to open the String List editor, where you can edit, add, or delete lines.

You can also work with string-list objects at run-time to perform such tasks as:

See Also