How to use 7z.dll? - dll

Question

I have now a script to download a file and copy to a directory. But how could i make it so that if i compress a folder to a zip file , and then would need to extract it when that zipped folder is downloaded. It's takes too much time to to write the lines for every file separately. I know that i could use 7z.dll to decompress, but dont know how to put that in code.
[Code]
procedure InitializeWizard;
begin
idpDownloadAfter(wpReady);
end;
procedure CurPageChanged(CurPageID: Integer);
begin
if CurPageID = wpReady then
begin
idpClearFiles;
if IsComponentSelected('IGR') then
idpAddFile('http://www.mediafire.com/download/f9hnlkt1t75ykjk/waterfall_IGR.model', ExpandConstant('{tmp}\waterfall_IGR.model'));
end;
end;
procedure CurStepChanged(CurStep: TSetupStep);
begin
if CurStep = ssPostInstall then
begin
// Copy downloaded files to application directory
FileCopy(ExpandConstant('{tmp}\waterfall_IGR.model'), ExpandConstant('{app}\res_mods\0.8.10\content\Environment\env_waterfall\waterfall_IGR.model'), false);
end;
end;

Answer 1

I dont know if 7z.dll will work directly, but what can be done is to download 7zip portable, include its folder in your package and pass the unzipping command to 7za.exe .
Eg :
7za.exe x <path to>\in.zip -oc:\pathToOutFolder

Answer 2

I had the same problem when create a 7zip file and split it out in several smnall files using the -v option, the way I fixed is using powershell I get the list of files and the create dynamically the Inno project, it looks something like
$Files = Get-Item "$zipFilesLocation\*.*"
$files | Select-object #{Name="Address"; Expression={"idpAddFile('<webaddress>" + $_.Name + "' , ExpandConstant('{tmp}\58-Formulary_201311.7z.001'));"}}
and tghen just write each object into the iss file like
foreach ($elem in $files)
{
$e = "idpAddFile( WebWrlString + '" + $elem.Name + "', ExpandConstant('{tmp}\" + $elem.Name + "'));"
$e | Out-File "Innopackage.iss" -Encoding ASCII -Append
}
I hope this helps