Borland Delphi one-sentence help

1.
If you want yourProgramIf you can correctly handle exceptions, Please reference the sysutils. Pas unit. Otherwise, even if the program uses try... exceptions t..., the exception cannot be correctly captured.

2. String constant array Initialization
Const constarray: array [0 .. 2]
String = ('first ', 'second', 'third ');

3. struct Initialization
Type
Tstructinit = record
A1: integer;
A2: array [0 .. 2] of integer;
End;

Const m_structinit: tstructinit = (A1: 0; a2 :( 0, 1, 2 ));

4. Length of multi-dimensional array

VaR array2: array of integer;
Setlength (array2, 2, 2 );

5. The space opened using create and new exists in the heap and cannot be automatically released. We recommend that you use freeandnil to release the space.

6.
Sizeof is not suitable for objects and always returns 4; it can return a correct value for a fixed type.

7.
Create (NiL) needs to be released manually, and creat (Self) will be released with the release of the owner.

8.
Downto is used repeatedly during the delete operation to avoid errors.

9. the ASCII code of a Chinese character> 128, which can be used to determine whether it is a Chinese character.

10. postmessage only stores messages in the message queue and needs to be queued for processing.

Sendmessage is directly sent to the window without passing through the message queue, and is returned only after the message is returned.

11. Move the mouse in and out of the message: cm_mouseenter, cm_mouseleave.

12. Send a message to get the number of all files in a directory and display the file names of all files in The ListBox control.
Const
Dirattr
= Ddl_readwrite or ddl_readonly or
Ddl_archive;

Listbox1.items. Clear;
Sendmessage (listbox1.handle,
Lb_dir, dirattr, INTEGER (pchar ('C /*.*')));
Filenum: =
Listbox1.items. count;