Solved: Replacing characters in PWideChar variable

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redsg

Replacing characters in PWideChar variable

I'm looking for a way to find and replace certain characters within a PWideChar variable in Delphi. The PWideChar variable contains Unicode (specifically, Chinese) characters, with which I'm looking to rename my files with. However, for some of these PWideChar variables, some special characters have been included, such as the colon (':').

How do I then find these special characters, and replace them with say an empty string? I'm aware of how to do this with normal String variables, but how can it be achieved with PWideChar variables?

Your assistance will be much appreciated please. Thanks!

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Pramod Bugudai🇮🇳

Hi. Each and every character has a unique UTF8 and UTF16 specific numbers. Like the colon character also has specific no. Also they have their decimal code points.
use this numbers to handle the characters. From a paragraph you can search for a character with it's unique decimal code points. So that you can easily handle them.

I will also suggest you to use WideChar(parameter as a num); for better results.

Here you can convert the characters to their unicode specific nos.
http://people.w3.org/rishida/scripts/uniview/conversion.php

Pramod Bugudai🇮🇳

remember WideChar() holds a single character that supports International character sets as it's parameter.

redsg

ASKER

pramodbugudai,

Thanks for your suggestions. The issue I'm facing now is manipulating the PWideChar variable itself. I'm quite new with Delphi, and even newer with the PWideChar type. I'm therefore looking for a reference with which can be used to manipulate PWideChar variables, much like how String variables can be manipulated i.e. the methods, properties etc.

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Hypo🇸🇪

You can always use a temporary string variable, in to which you load the values from the PWideChar, and then use the functions that you are familiar with to do what you want, and when you are done write the result back to the PWideChar...

Delphi handles typecasting from a Widestring to a PWideChar as long as you tell it to...

regards
Hypo

uses ..., StrUtils; 
procedure TForm1.Button1Click(Sender: TObject);
var aWideChar : PWideChar;
    aTempString : WideString;
begin
  // Load the PWideChar-string with some data... 
  aWideChar := '123:321';
  // Move the PWideChar-string into a temp-string...   
  aTempString := aWideChar;
  // Do your stuff... 
  aTempString := ReplaceStr(aWideChar, ':', ' ');
  // Reload the PWideChar with the contents of the string... 
  aWideChar := PWideChar(aTempString);
  // Show results... 
  ShowMessage(aWideChar);
end;

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redsg

ASKER

Hypo,

I tried the following:

var
tempName: WideString;
newName: PWideChar
...
newName := PWideChar(TntMemo1.Lines.Strings[index]);
tempName := newName;
tempName := StringReplace(newName, ':', ' ');
newName := PWideChar(tempName);

But when I tried to show the results within another TNTMemo object, the Chinese characters have all been converted to "?"s. I think this occured when the PWideChar variable is changed to the WideString type (i.e. tempName := newName).

redsg

ASKER

An update - casting from PWideChar to WideString did not change the characters to "?"s, instead, its after going through the "StringReplace" method that the characters turn out as "?"s.

I noticed that u used the "ReplaceStr" method, what do I need to add to the "Uses.." statement to use this method?

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redsg

ASKER

Found a sort-of workaround i.e. by "splitting" the WideString variable. Before that, I looked for the position of the character(s) concerned, and if found the method attached below is triggered.

Everything seems to work fine for now.

function SplitString(pos: Integer; str: WideString): WideString;
var
   left:   WideString;
   right: WideString;
begin
   left := LeftStr(str, pos-1);
   right := RightStr(str, Length(str)-pos);
   Result := left + right;
end;

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ASKER CERTIFIED SOLUTION

Hypo🇸🇪

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redsg

ASKER

Thanks for your help Hypo!

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