[Lazarus] String vs WideString

[Michael Schnell]

On 15.08.2017 12:11, Mattias Gaertner via Lazarus wrote:
> It does not explain what the characters of DynamicString are, does it? 

I don't understand what you are asking.

The element size and encoding of a Dynamic String ("CP_ANY" in the 
document) are not predefined, but depend on the content:

http://wiki.freepascal.org/not_Delphi_compatible_enhancement_for_Unicode_Support 
-> Defining String variables and String types:
> *CP_ANY* = $FF00 // ElementSize dynamically assigned // fully 
> dynamical String for intermediate storing string content // just 
> assigned to the Type or variable, never used in the "Encoding" field 
> in the string header. 


Hence it stores the "branding" when it is assigned to from a string with 
a fixed branding (such as *CP_UTF8*), and the content is auto-converted 
if necessary when  assigning form CP_ANY to a fixed branded string variable.


If (in your example) the data is read from a file, a CP_ANY Strings 
based StringList would keep the encoding/char_size of the data as t is 
in the file (it would need to somehow get to know the presumed encoding 
of the file, anyway) and store that information in the 
EncodingBrandNumber and ElementSize fields (which do exist in any 
"NewString" variable, anyway), in each String read.

If the user assignes an element of the stringlist to a fixed branding 
(such as *CP_UTF8*),  the content obviously is auto-converted if 
necessary when  assigning form CP_ANY to a fixed branded string 
variable, as usual.

In fact I suppose that the current implementation of TStringlist does 
not use new strings to store the data on the heap, but I never said that 
trying to implement such idea would not require a lot of work.

-Michael
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