Hi,
I seek help to clarify a very basic use of TStringList.
Let A and B be TStringLists. What is the difference between:
A:=B;
and
A.Assign(B); ?
That's more a basic(?) question about Pascal.
When you do A:=B; then A has become equal to B. That means for example
that if you add an new string to B, this new string will also be in A.
After all A and B are the same.
Note that if A contained a TStringList that you can not acces it anymore
through A, but it's still present in memory.
When you do A.Assign(B); then all strings in A are cleared and
afterwards all strings in B are copied to A. Further all relevant
properties of B are also set to A.
Note that in this case, A should already contain a TStringList, and if
you add values to B after the assignment, those strings will not appear
in B.
In other words: When you declare
A, B : TStringList;
you actually allocated two pointer to TStringList since classes are
inherently pointers. When you do "A:=B" you now have A pointing to the
same memory space as B. It's a pity you can't do "A^ := B^;"
Andreas
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