运算符sizeof

sizeof() operator returns the total number of size occupied by a variable, since array is also a variable, we can get the occupied size of array elements.

sizeof()运算符返回变量占用的大小总数，由于array也是变量，我们可以获取数组元素占用的大小。

逻辑 (Logic)

Get the occupied size of all array elements and divide it with the size of array type. Let suppose there is an integer array with 5 elements then size of the array will be 5*4=20 and the size of array type will be 4. Divide 20 by the 4 answer will be 5 which is the number of array elements.

获取所有数组元素的占用大小，然后将其除以数组类型的大小。 假设有一个包含5个元素的整数数组，那么数组的大小将为5 * 4 = 20，数组类型的大小将为4。20除以4的答案将为5，这是数组元素的数量。

Let's consider the following program

让我们考虑以下程序

程序计算C语言中数组元素的总数 (Program to count total number of array elements in C)

#include <stdio.h>
int main()
{
int arr[]={10,20,30,40,50};
int n;
n=sizeof(arr)/sizeof(int);
printf("Number of elemenets are: %d\n",n);
return 0;
}

Output

输出量

Number of elemenets are: 5

另一种方法 (Another method)

We can divide the occupied size of all array elements by size of any one array element. Consider the following statement:

我们可以将所有数组元素的占用大小除以任何一个数组元素的大小。 考虑以下语句：

n=sizeof(arr)/sizeof(arr[0]);

翻译自: https://www.includehelp.com/code-snippets/c-program-to-count-array-elements-by-using-sizeof-operator.aspx

运算符sizeof