To avoid dangling Pointers (the dangerous situation where a block of memory is freed but a pointer still references it), you must delete the object only after the last reference is released.

为了避免悬空指针(一种危险的情况，即一块内存已经被释放了，而一个指针还在引用它)，必须在最后的引用释放之后才删除对象。

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For example, if you click while pointing to a block header entry, the shortcut menu shows the New Version block Info and Delete Version block Info commands.

例如，如果在指向块头项时单击，快捷菜单将显示“新建版本信息区”和“删除版本信息区”命令。

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