Qt中查看cpu使用和mem使用情况方法

基于 https://blog.youkuaiyun.com/yangyang031213/article/details/79023536 修改测试通过

#include <QProcess>

void MainWindow::get_procinfo()
{
    QProcess process;
    process.start("free -m"); //使用free完成获取
    process.waitForFinished();
    process.readLine();
    QString str = process.readLine();
    str.replace("\n","");
    str.replace(QRegExp("( ){1,}")," ");//将连续空格替换为单个空格 用于分割
    QStringList lst = str.split(" ");
    if(lst.size() > 3)
    {
        QString str2;
        //str2.sprintf("mem total:%.0lfMB free:%.0lfMB",lst[1].toDouble(),lst[3].toDouble());
        double mem_rate =(lst[1].toDouble() -lst[3].toDouble()) / lst[1].toDouble() * 100.0;
        str2.sprintf("mem rate:%.2lf%%",mem_rate);
        ui->label_2->setText(str2);
        //qDebug("mem total:%.0lfMB free:%.0lfMB",lst[1].toDouble(),lst[3].toDouble());
        qDebug("mem rate:%.2lf%%",mem_rate);
}

void MainWindow::get_cpu()
{

    QProcess process;
    double cpu_total=0;
    double cpu_use=0;
    process.start("cat /proc/stat");
    process.waitForFinished();
    QString str = process.readLine();
    str.replace("\n","");
    str.replace(QRegExp("( ){1,}")," ");
    QStringList lst = str.split(" ");
    if(lst.size() > 3)
    {
        double use = lst[1].toDouble() + lst[2].toDouble() + lst[3].toDouble();
        double total = 0;
        double cpu_rate=0;
        for(int i = 1;i < lst.size();++i)
            total += lst[i].toDouble();
        if(total - m_cpu_total > 0)
        {
            QString str1;
            cpu_rate = (use - cpu_use) / (total - cpu_total) * 100.0;

            str1.sprintf("cpu rate:%.2lf%%",cpu_rate);
            qDebug("cpu rate:%.2lf%%",cpu_rate);
            ui->label_4->setText(str1);
            m_cpu_total = total;
            m_cpu_use = use;
        }
    }
}