TStringList CustomSort method on Name/Value pairs

Question

Is is posssible to use customSort on a TStringList using the Name from the Name/Value pairs

I was currently using a TStringList to sort one value in each pos. I now need to add additional data with this value and therefor I am now using the TStringList as Name/Values

My current CompareSort is:

function StrCmpLogicalW(sz1, sz2: PWideChar): Integer; stdcall;
  external 'shlwapi.dll' name 'StrCmpLogicalW';


function MyCompare(List: TStringList; Index1, Index2: Integer): Integer;
begin
  Result := StrCmpLogicalW(PWideChar(List[Index1]), PWideChar(List[Index2]));
end;
Usage:
  StringList.CustomSort(MyCompare);

is there a way to modify this so that it sorts based on the Name of the name value pairs?

Or, is there another way?

score 8 · Accepted Answer · answered Mar 19 '13 at 17:08

8

function MyCompare(List: TStringList; Index1, Index2: Integer): Integer;
begin
  Result := StrCmpLogicalW(PWideChar(List.Names[Index1]), PWideChar(List.Names[Index2]));
end;

But actually, I think yours should work as well, since the string itself starts with the name anyway, so sorting by the entire string implicitly sort it by name.

answered Mar 19 '13 at 17:08

GolezTrol

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Where is this function? – Adrian Maire Jun 28 '23 at 07:37
@AdrianMaire What function? MyCompare is mine StrCmpLogicalW is an Windows API function declared in the question. – GolezTrol Jun 28 '23 at 18:02

score 4 · Answer 2 · answered Mar 19 '13 at 17:08

To solve this you use the Names indexed property which is described in the documentation like this:

Indicates the name part of strings that are name-value pairs.

When the list of strings for the TStrings object includes strings that are name-value pairs, read Names to access the name part of a string. Names is the name part of the string at Index, where 0 is the first string, 1 is the second string, and so on. If the string is not a name-value pair, Names contains an empty string.

So, instead of List[Index1] you simply need to use List.Names[Index1]. Your compare function thus becomes:

function MyCompare(List: TStringList; Index1, Index2: Integer): Integer;
begin
  Result := StrCmpLogicalW(
    PChar(List.Names[Index1]), 
    PChar(List.Names[Index2])
  );
end;

TStringList CustomSort method on Name/Value pairs

2 Answers2

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