CODEWITHSUNDEEP
delphidelphi-7
Mohammad Arif
Mohammad Arif

Reputation: 21

Run open file with Opendialog and execute it

I want to do something like this: 

ShellExecute(0, nil, PChar('E:\generic\mpv\mpv.exe'), PChar(''+TntOpenDialog1.FileName+''), nil, SW_HIDE);

but nothing happened.
When I try to do something with code like this:

TntLabel1.Caption:=PChar(TntOpenDialog1.FileName);

it just shows me the first letter of file which I selected before.
How can I solve this problem?

Upvotes: 0

Views: 1267

Answers (2)

David Heffernan
David Heffernan

Reputation: 612794

You've got an encoding mismatch:

  • TntOpenDialog1.FileName is UTF-16 encoded.
  • PChar is an alias for PAnsiChar and so is ANSI.
  • ShellExecute is an alias for ShellExecuteA, the ANSI variant.

This means that you are passing UTF-16 data to a function that expects ANSI encoded text. Hence the observed behaviour.

Replace PChar with PWideChar and ShellExecute with ShellExecuteW to correct that mismatch.

In the first instance, to convince yourself that this is the problem, change your debugging code to this:

TntLabel1.Caption := PWideChar(TntOpenDialog1.FileName);

Use ShellExecuteExW if you wish to be able to report errors properly. Use CreateProcessW to create the process directly and avoid involving the shell.

If

'' + TntOpenDialog1.FileName + ''

is not a typo from when you wrote the question, then that's a problem too. Because '' is just the empty string.

In other words, that expression is equal to

TntOpenDialog1.FileName

You would need to use:

'"' + TntOpenDialog1.FileName + '"'

in order to quote the argument and escape any space characters.

Upvotes: 2

moskito-x
moskito-x

Reputation: 11958

if you space in the file path expect, you can not pass a param like ''+myparam+''

var
myparam : AnsiString;
begin
myparam := 'test file nr 10.txt';
ShellExecute(0, nil, PChar('...'), PChar(''+myparam+''), nil, SW_HIDE);

ParamStr(1) will give you only test !!

If you have spaces in the path use it like:

ShellExecute(0, nil, PChar('...'), PChar('"'+myparam+'"'), nil, SW_HIDE);

Try following. but take care with the cast from FFileName: WideString to AnsiString, information may be lost. Use this only if there are no special characters in the file path occur.

...
var
AnsiStr : AnsiString;
...
begin

AnsiStr := TntOpenDialog1.FileName;
ShellExecute(0, nil, PChar('E:\generic\mpv\mpv.exe'), PChar('"'+AnsiStr+'"'), nil, SW_HIDE);

Upvotes: -1

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