SHGetFolderPath Causes exception

Hi there,

In an attempt to make my software more Vista compatable, I am using SHGetFolderPath to get the AppData folder so I can then create a subfolder and write to it.

Now, my application has two forms, on the first form I have this in the oncreate method in the first form.


  If SHGetFolderPath(0, CSIDL_APPDATA, 0, 0, P) = S_OK then
      gbSavePath := P +  '\MySubFolder\';
  else
    gbSavePath := GetCurrentDir;

yes I have added SHFolder to the uses clause, and the oncreate method on the second form is blank.

now, i know that gbSavePath gets set with the correct location, but when my secord for is created - an exception occurs.
I comment that code above, and everything runs fine.

Confused!
LVL 10
wildzeroAsked:
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wildzeroAuthor Commented:
However doing this is fine
const
   SHGFP_TYPE_CURRENT = 0;
var
  path: array [0..255] of char;
begin
  If SHGetFolderPath(0,CSIDL_APPDATA,0,SHGFP_TYPE_CURRENT,@path[0]) = S_OK then
      gbSavePath := Path +  '\MySubFolder\'
  else
    gbSavePath := GetCurrentDir;

With no worries
hmmm
0
ziolkoCommented:
If SHGetFolderPath(0, CSIDL_APPDATA, 0, 0, P) = S_OK then
      gbSavePath := P +  '\MySubFolder\';

what type is variable: P?

ziolko.
0
ziolkoCommented:
...and more important how P is initialized?
ziolko.
0
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wildzeroAuthor Commented:
var
P : Pchar;
begin
sorry :-)
0
ziolkoCommented:
if you use PChar you need to allocate it
so it have enough space to store path and  '\MySubFolder\'
and then remember to deallocate it's a lot easier to use it
like in second sample witch array of char, using array
is very common with Windows API and null terminated strings

ziolko.
0
wildzeroAuthor Commented:
if you use PChar you need to allocate it

Care to show how :-)
Points upped
0
ziolkoCommented:
two ways:

GetMem(P, ...)
FreeMem(P)

or

P := StrAlloc(...)
StrDispose(P)

ziolko.
0

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