System.Classes.TStringListSortCompare

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Delphi

TStringListSortCompare = function(List: TStringList; Index1, Index2: Integer): Integer;

C++

typedef int __fastcall (*TStringListSortCompare)(TStringList* List, int Index1, int Index2);

Properties

Type Visibility Source Unit Parent
type
typedef
public
System.Classes.pas
System.Classes.hpp
System.Classes System.Classes

Description

TStringListSortCompare is a type of callback function called used internally by the TStringList class.

You define a TStringListSortCompare function when you need to use the TStringList CustomSort method. The procedure defined by TStringListSortCompare is invoked by CustomSort to sort the TStringList elements into sequence.

CustomSort is used instead of Sort when the sort sequence required differs from the default alphanumeric sequence.

List is the list of strings.

Index1 and Index2 are indexes into the list. When these are passed to the TListSortCompare function, the CustomSort method is asking which order they should be in.

You return 0 if the entry referred to by Index1 equals the entry referred to by Index2

You return less than 0 if the entry referred to by Index1 is less than the entry referred to by Index2

You return a number above 0 if the entry referred to by Index1 is greater than the entry referred to by Index2

Note: One of the principle advantages of the CustomSort method is that a TStringList may be sorted according to the objects optionally attachable to each string.

See Also