Edit JSON array with Inno Setup - json

Question

I want to edit a JSON file with Inno Setup for entering the installation path of my programme.
I have also found the post: How to parse a JSON string in Inno Setup? however, I can't cope with it because it talks about Info, User & String, but I only have Info & User.
This is what the entry that needs to be edited looks like:
"game_dirs": [
"Installation path"
]
This is my code:
[Code]
function JSONQueryString(FileName, Section, Key, Default: WideString;
var Value: WideString; var ValueLength: Integer): Boolean;
external 'JSONQueryString#files:jsonconfig.dll stdcall';
function JSONQueryBoolean(FileName, Section, Key: WideString;
Default: Boolean; var Value: Boolean): Boolean;
external 'JSONQueryBoolean#files:jsonconfig.dll stdcall';
function JSONQueryInteger(FileName, Section, Key: WideString;
Default: Int64; var Value: Int64): Boolean;
external 'JSONQueryInteger#files:jsonconfig.dll stdcall';
function JSONWriteString(FileName, Section, Key,
Value: WideString): Boolean;
external 'JSONWriteString#files:jsonconfig.dll stdcall';
function JSONWriteBoolean(FileName, Section, Key: WideString;
Value: Boolean): Boolean;
external 'JSONWriteBoolean#files:jsonconfig.dll stdcall';
function JSONWriteInteger(FileName, Section, Key: WideString;
Value: Int64): Boolean;
external 'JSONWriteInteger#files:jsonconfig.dll stdcall';
function BoolToStr(Value: Boolean): string;
begin
Result := 'True';
if not Value then
Result := 'False';
end;
procedure InitializeWizard;
var
FileName: WideString;
IntValue: Int64;
StrValue: WideString;
StrLength: Integer;
BoolValue: Boolean;
begin
{ set the source JSON config file path }
FileName := '{app}\\PATH\\Config.json';
{ allocate string buffer to enough length }
SetLength(StrValue, 16);
{ set the buffer length value }
StrLength := Length(StrValue);
{ query string value }
if JSONQueryString(FileName, 'game_dirs', '{app}\TEST', 'Default', StrValue,
StrLength)
then
MsgBox('Section_1:Key_1=' + StrValue, mbInformation, MB_OK);
{ query integer value }
if JSONQueryInteger(FileName, 'Section_1', 'Key_2', 0, IntValue) then
MsgBox('Section_1:Key_2=' + IntToStr(IntValue), mbInformation, MB_OK);
{ query boolean value }
end;
The following error message appears during installation:
Runtime error (at 46:224): Could not call proc.

Answer 1

Your game_dirs element is a JSON array. I do not think that JSONConfig.dll supports arrays.
You can use JsonParser library instead. With use of additional functions from my answer to How to parse a JSON string in Inno Setup?, the code can be like:
function FindJsonArray(
Output: TJsonParserOutput; Parent: TJsonObject; Key: TJsonString;
var Arr: TJsonArray): Boolean;
var
JsonValue: TJsonValue;
begin
Result :=
FindJsonValue(Output, Parent, Key, JsonValue) and
(JsonValue.Kind = JVKArray);
if Result then
begin
Arr := Output.Arrays[JsonValue.Index];
end;
end;
procedure EditGameDirs(FileName: string; GameDir: string);
var
JsonLines: TStringList;
JsonParser: TJsonParser;
JsonRoot: TJsonObject;
GameDirs: TJsonArray;
begin
JsonLines := TStringList.Create;
JsonLines.LoadFromFile(FileName);
if ParseJsonAndLogErrors(JsonParser, JsonLines.Text) then
begin
JsonRoot := GetJsonRoot(JsonParser.Output);
if not FindJsonArray(JsonParser.Output, JsonRoot, 'game_dirs', GameDirs) then
begin
Log('Cannot find game_dirs');
end
else
if (GetArrayLength(GameDirs) <> 1) or
(GameDirs[0].Kind <> JVKString) then
begin
Log('game_dirs does not have one string element');
end
else
begin
Log(Format('Previous game_dirs was [%s]', [
JsonParser.Output.Strings[GameDirs[0].Index]]));
Log(Format('New game_dirs is [%s]', [GameDir]));
JsonParser.Output.Strings[GameDirs[0].Index] := GameDir;
JsonLines.Clear;
PrintJsonParserOutput(JsonParser.Output, JsonLines);
JsonLines.SaveToFile(FileName + '2');
end;
end;
end;