Name
UniqueString Procedure
Syntax
procedure UniqueString(var Str: string);
Description
The UniqueString
procedure ensures that
Str
has a reference count of one. If
Str
has no other references,
UniqueString
leaves it alone; otherwise,
UniqueString
allocates a new copy of the string
and assigns that unique copy to
Str
.
UniqueString
is a real procedure.
Tips and Tricks
You do not usually need to call
UniqueString
. Delphi uses copy-on-write semantics for strings, so if you have multiple references to a string and you modify the string through one reference, Delphi automatically creates a unique string to modify, so the other references continue to refer to the original string.If you cast a
string
toPChar
, Delphi also ensures that thePChar
points to a unique instance of the string. If you modify the string through thePChar
pointer, the other references to the original string are safe.
See Also
String Keyword |
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