C/C++获取Windows平台CPU占用率的方法

#include <pdh.h>
#pragma comment(lib, "Pdh.lib")
 
PDH_STATUS status;
PDH_HQUERY query;
PDH_HCOUNTER counter;
 
status = PdhOpenQueryA(NULL, 0, &query);
if (status != ERROR_SUCCESS) {
    return;
}
        
status = PdhAddCounterA(query, "\\Processor(_Total)\\% Idle Time", 0, &counter);
if (status != ERROR_SUCCESS) {
    PdhCloseQuery(query);
    return;
}
 
const int NUM = 10;
PdhCollectQueryData(query);
PDH_RAW_COUNTER rawValueArray[NUM]; // 假设有00个取样值
for (int i = 0; i < NUM; i++)
{
    Sleep(1000);    //阻塞1s
    PdhCollectQueryData(query);
 
    PDH_FMT_COUNTERVALUE value;
    PdhGetRawCounterValue(counter, 0, &rawValueArray[i]);
    status = PdhGetFormattedCounterValue(counter, PDH_FMT_DOUBLE, NULL, &value);
    if (status == ERROR_SUCCESS) {
        printf("getCpuPercenage: %.2f%\n", value.doubleValue);
    }
    else {
        std::cout << "Error:" << status;
    }
}
        
DWORD dwFirstEntry = 0; // 从第一个取样值开始
DWORD dwNumEntries = NUM; // 一共10个取样值
PDH_STATISTICS stat;
// 计算统计信息
status = PdhComputeCounterStatistics(counter, PDH_FMT_DOUBLE, dwFirstEntry, dwNumEntries, rawValueArray, &stat);
 
if (status == ERROR_SUCCESS) {
    printf("Average: %f\n", stat.mean.doubleValue);
    printf("Minimum: %f\n", stat.min.doubleValue);
    printf("Maximum: %f\n", stat.max.doubleValue);
}
else {
    printf("Failed to compute counter statistics: %d\n", status);
}
        
PdhCloseQuery(query);