If FileExists(

[lgrfbs]

Hi, I’ve been away from the forum for a while and apparently missed a few things.
I’m stuck on how to check if a file exists.
I think you need some code to handle the “\” character as well.

Code: Pascal  [Select][+][-]

1. procedure TForm1.FormPaint(Sender: TObject);
2. Var
3. Index:Byte;
4. T: String;
5.  
6. begin
7.  if ParamCount>1 then Begin
8.     //https://forum.lazarus.freepascal.org/index.php?topic=15715.0
9.     T:='';
10.     TabSheet2.Enabled:=True; //Debug
11.     For Index:=1 to ParamCount do
12.     Begin
13.      T:=T+' '+ParamStr(Index);
14.     End;
15.     LabeledEdit1.Text:=T; //ParamStr(1);
16.  
17.     Label9.Caption:=T+'\NC_clean.ini'; //IntToStr(ParamCount);
18.     If FileExists(T+'\NC_clean.ini') Then
19.     Begin
20.      ShowMessage('All is well, I seem to exist.'); //For test
21.      //TabSheet2.Enabled:=True;
22.     End;
23.  end;
24. end;
25.  

I hope this post includes all the necessary information.
So what should I look for to get the program code to “recognize” that the file exists?

[ASerge]

I hope this post includes all the necessary information.

I didn't understand what you want to say and what FileExists has to do with it.

[lgrfbs]

Sorry for the confusion.
I wanted to find out the best way to check a path.

[Xenno]

Use IncludeTrailingPathDelimiter which takes care to add path delimiter when needed.

Code: Pascal  [Select][+][-]

1. FullPath := IncludeTrailingPathDelimiter(T) + 'NC_clean.ini';

[hukka]

Your code is adding a space to the beginning of the path.

[lgrfbs]

It's working now.
I am deeply grateful for the help I've received.
THANK YOU, everyone

[Bart]

Use IncludeTrailingPathDelimiter which takes care to add path delimiter when needed.

Code: Pascal  [Select][+][-]

1. FullPath := IncludeTrailingPathDelimiter(T) + 'NC_clean.ini';

Notice that this is wrong if T is in the form of DriveLetter + Colon ('C:'), since IncludeTrailingPathDelimiter will append the '\', which most likely is not what you want then.

IIRC then AppendPathDelim (somewhere in LazUtils) caters for that.

I know it's an edge case.

Bart

[Remy Lebeau]

Notice that this is wrong if T is in the form of DriveLetter + Colon ('C:'), since IncludeTrailingPathDelimiter will append the '\', which most likely is not what you want then.

Why? If a user wants to refer to a file on 'C:' then they likely really mean 'C:\<file>' rather than 'C:\<cwd>\<file>'. Using 'C:' without a slash to refer to C's current working directory is a lost art on modern generations of users.

IIRC then AppendPathDelim (somewhere in LazUtils) caters for that.

Not according to this documentation:

Windows

Please note that a value like 'C:' in Path results in 'C:\' in the return value. AppendPathDelim does not access the disk device to determine the per-device current directory; it simply appends the trailing path delimiter to the return value.

[Bart]

Why? If a user wants to refer to a file on 'C:' then they likely really mean 'C:\<file>' rather than 'C:\<cwd>\<file>'. Using 'C:' without a slash to refer to C's current working directory is a lost art on modern generations of users.

I disagree: 'C:Foo' in almost every case will not be the same as C:\Foo.
(I'm from the DOS era).

IIRC then AppendPathDelim (somewhere in LazUtils) caters for that.

Not according to this documentation:

My bad.
Was too lazy to actually check the source code.

Bart

[PascalDragon]

Why? If a user wants to refer to a file on 'C:' then they likely really mean 'C:\<file>' rather than 'C:\<cwd>\<file>'. Using 'C:' without a slash to refer to C's current working directory is a lost art on modern generations of users.

I disagree: 'C:Foo' in almost every case will not be the same as C:\Foo.
(I'm from the DOS era).

But it's true that many (new) users don't know about that functionality. Or drive absolute paths (\some\path). Even VS 2022 doesn't allow entering them for files contained in the project anymore while past versions did (though it at least keeps them if adjusted in the project file).

[Bart]

I'm getting way too ancient 

Bart

[Remy Lebeau]

I disagree: 'C:Foo' in almost every case will not be the same as C:\Foo.
(I'm from the DOS era).

Yes, that is how the OS actually handles it under the hood. But, I was referring to it from a user perspective. Modern users don't operate at that level anymore, and most UIs don't work that way, either. In fact, a common advice given in forums is to never rely on relative paths anymore when opening files, always use absolute paths only. So, opening a file using 'C:\Foo' would be far more common than using 'C:Foo'.