[Reply]
HI Gajo,
In essence it should work, however thinking beyond what you have described, the
following may help.
The array, when created (or extended using setlength(myArray,i+1).. etc), should have
each new item set to nil. You can test this in two ways:
if (myArray[i] = nil) then ...
or
if assigned(myArray[i]) then ...
The catch is, that each item is a pointer to a memory location, and after the object
instance is created, will point to the location of the memory allocated bu the OS to
the object instance. If that object is freed (myArray[i].free) then the memory is
deallocated by the OS (Windows), but the array item still points to that location in
memory that was allocated.
So for this to work, you also need to reset the array pointer, eg
myArray[i].free;
myArray[i] := nil;
or
freeAndNil(myArray[i]);
Then the array item is reset to nil, and the tests above will continue to work.
kind regards
Gary
| To : [EMAIL PROTECTED]
| CC :
| From: Gajo Istvan, [EMAIL PROTECTED]
| Content Type: text/plain
| Attached:
|
| Hi,
| I have an array of TObjects. A cell of the array may not have been created,
| so I want to check if it exists or not. This doesn't work:
| if myArray[i] = nil then ShowMessage('Object doesn't exist')
|
| What should I do?
| Gajo
|
|
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