I'm using Qt and C++, I need to find out the amount of memory used by instances of certain Qt classes, this is usually done using sizeof, however in Qt each class holds a pointer to an another class containing the actual implementation, the definition of this private implementation class is not found in headers but only in the source-code. Web26 rows · Detailed Description. A size is specified by a width () and a height (). It can be set in the ...
既然数组的指针的指针类型是int (*)[10] 那为什么p1++不是&a+sizeof…
WebNov 11, 2024 · As this is a compiler error and 'sizeof' is a compiler function that works on declared types, the error is of cause explainable. In the header file the array is not initialized and its size is not specified. The header file is the only thing the compiler knows when compiling the sketch. The cpp file is compiled to an object file in another step. Web1. Qt supports many platforms, but what matters is the platform's 64-bit data model (or probably more correctly, the compiler plus platform's data model). Most common 64-bit … shrm adult learning
编写程序，通过调用sizeof()函数查看指针变量的大小，并由此判断 …
WebNov 26, 2012 · It has two attributes: an integer (4 bytes) and a boolean (1 byte). struct SampleStruct { bool flag; unsigned int timeout; }; If we get the instance size using sizeof we should get 5 bytes size and memory would be like: Figure 1. 5 bytes struct which uses 5 bytes in memory But is not that simple, memory alignment depends on compiler and … WebJun 28, 2011 · sizeof is ok, it's about aligning the data structure members for efficient access, read this article for more details: Data structure alignment Your second example is ok (both are), sizeof (short) = 2. To encourage you for further reading, consider this example: Qt Code: Switch view struct AA { float a; unsigned char metadata; float a2; WebJul 2, 2015 · This uses the staticMetaObject of the class (as declared in the Q_OBJECT macro). The function can just be called by getFooBarMetaObject (); (without the FooBar:: that would be required if it was a static function instead of a friend). With that we can now construct the Q_ENUM macro: #define Q_ENUM (ENUM) \. friend constexpr const … shrm affirmative action plan template