The handle is some of the indexes of tables, but the plugs, handles, and pointers are the address, and the handle is a key concept of Windows programming. Writing a Windows application is always dealing with various handles. The so-called handle is a unique number to identify many different object types such as windows, menus, memory, brush, painting, telephone line, etc. In Win32, the handle is a pointer to a "non-type object" (void *), which is a 4-byte long data. No matter what it is, the handle is not a true pointer. From the configuration, the handle is a pointer, although it does not point to the memory location for storing an object. In fact, the handle points to a location that contains the reference to the object. The statement of the handle is this: typedef void * handle Because Windows is a multi-task operating system, it can run multiple copies of multiple programs or a program at the same time. These operational programs are called an example. In order to manage multiple copies of the same program, Windows introduces an instance handle. Windows establishes a table for each application, and the instance handle is like an index of this table. Different lies in: 1. The handle can be a very complex structure, and it can be related to the system, such as the handle of the thread described above, it points to a very class, he and the system There is a close relationship, when a thread is unpredictable reason, while the system can return to the information it occupied in the system, such as CPU, memory, etc., in turn, I want to know, some items in this handle, It is interacting with the system. Due to the Windows system, it is a multi-task system that may allocate memory, recycle memory, and restructuring memory. 2, the pointer can also point to a complex structure, but is usually user-defined, so the required work must be done, especially when deleting. However, there are also some pointers in VC 6.0, which are handled for some small problems, such as pointers such as the most common characters, which also wants to handle memory, but cstring does not handle users, It is actually a class in VC , so the operation is completed by the member function, generating (allocation) is completed by the constructor, deleting (recycling) by the destructor.
