什么是“表达式必须具有类类型"?错误是什么意思? [英] What does "expression must have class type" error mean?

问题描述

#include <cstdlib>
using namespace std;

int main()
{
    int arrayTest[512];
    int size = arrayTest.size();
    for(int a = 0;a<size;a++)
    {
         //stuff will go here
    }
}

在这里我在做什么错，因为该计划只是用一些数字填充数组

What am I doing wrong here becuase the plan is to just fill the array with some numbers

推荐答案

执行以下操作:

int arrayTest[512];
int size = sizeof(arrayTest)/sizeof(*arrayTest);

C样式的数组没有成员函数.他们没有阶级的概念.

C-style arrays don't have member function. They don't have any notion of class.

无论如何，更好使用std::array:

#include <array>

std::array<int,512> arrayTest;
int size = arrayTest.size();   //this line is exactly same as you wrote!

看起来像您想要的.现在，您可以使用索引i作为arrayTest[i]来访问arrayTest的元素，其中i的范围可以从0到size-1(包括).

which looks like what you wanted. Now you can use index i to access elements of arrayTest as arrayTest[i] where i can vary from 0 to size-1 (inclusive).

这篇关于什么是“表达式必须具有类类型"?错误是什么意思?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！