Qt開發(fā)之獲取電腦磁盤容量
項目中用到了監(jiān)測某磁盤（如：C盤、D盤等）的總?cè)萘亢涂捎萌萘?，查了一下，發(fā)現(xiàn)其實挺簡單，調(diào)用一個Windows自帶的API：GetDiskFreeSpaceEx( ... )就可以解決。用Qt做了一個測試?yán)?，如下所示?/p>
另：測試發(fā)現(xiàn)，如果給定路徑不存在（如程序中"F:\"），則獲取不到信息；通常給定用以獲取磁盤容量信息的路徑為“C:\”、"D:\"等，但給定已存在路徑（如程序中"D:\Test"），同樣可以獲取到該路徑所屬信息。
示例代碼：
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/*main.cpp*/??#include "acquirediskspace.h"#include <QtWidgets/QApplication>??int main(int argc, char *argv[]){????QApplication a(argc, argv);????AcquireDiskSpace w;????w.show();????return a.exec();}1
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/*acquirediskspace.h */??#ifndef ACQUIREDISKSPACE_H#define ACQUIREDISKSPACE_H??#include <QDialog>??class QLineEdit;??class AcquireDiskSpace : public QDialog{????Q_OBJECT??public:????AcquireDiskSpace( QWidget *parent = 0 );????~AcquireDiskSpace();??protected slots:????void slotDiskChanged( const QString& );??private:????void GetDiskSpace( QString strDisk, double& dTotalBytes, double& dFreeBytes );??private:????QLineEdit* m_pEdtTotalSpace;????QLineEdit* m_pEdtFreeSpace;};??#endif // ACQUIREDISKSPACE_H1
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/*acquirediskspace.cpp */??#include "acquirediskspace.h"??#include <QLabel>#include <QLineEdit>#include <QPushButton>#include <QComboBox>#include <QGridLayout>#include <QMessageBox>??#include "windows.h"??AcquireDiskSpace::AcquireDiskSpace( QWidget *parent )????: QDialog( parent ){????setWindowFlags( Qt::WindowTitleHint );????resize( 400, 400 );????setStyleSheet( "QDialog{background:white;}" );??????m_pEdtTotalSpace = new QLineEdit;????m_pEdtTotalSpace->setEnabled( false );????m_pEdtTotalSpace->setMinimumHeight( 30 );????m_pEdtFreeSpace = new QLineEdit;????m_pEdtFreeSpace->setEnabled( false );????m_pEdtFreeSpace->setMinimumHeight( 30 );??????//Disk????QComboBox* pCmbDisk = new QComboBox;????pCmbDisk->addItem( "C:/" );????pCmbDisk->addItem( "D:/Test" );????pCmbDisk->addItem( "E:/" );????pCmbDisk->addItem( "F:/" );????pCmbDisk->addItem( "G:/" );????pCmbDisk->setMinimumHeight( 30 );??????//Button????QPushButton* pBtnOK = new QPushButton( "OK" );????pBtnOK->setMinimumHeight( 30 );????QHBoxLayout* pBtnLayout = new QHBoxLayout;????pBtnLayout->addWidget( pBtnOK );??????//MainLayout????QGridLayout* pMainLayout = new QGridLayout;????pMainLayout->addWidget( new QLabel( "Total:" ), 0, 0, Qt::AlignRight );????pMainLayout->addWidget( m_pEdtTotalSpace, 0, 1 );????pMainLayout->addWidget( new QLabel( "GB" ), 0, 2 );??????pMainLayout->addWidget( new QLabel( "Free:" ), 1, 0, Qt::AlignRight );????pMainLayout->addWidget( m_pEdtFreeSpace, 1, 1 );????pMainLayout->addWidget( new QLabel( "GB" ), 1, 2 );????pMainLayout->addWidget( new QLabel( "Disk:" ), 2, 0, Qt::AlignRight );????pMainLayout->addWidget( pCmbDisk, 2, 1 );????pMainLayout->addLayout( pBtnLayout, 3, 1 );????setLayout( pMainLayout );??????//connects????connect( pCmbDisk, SIGNAL( currentIndexChanged( const QString& ) ), this, SLOT( slotDiskChanged( const QString& ) ) );????connect( pBtnOK, SIGNAL( clicked() ), this, SLOT( accept() ) );??????//Init????QString strDisk = pCmbDisk->currentText();????slotDiskChanged( strDisk );}??AcquireDiskSpace::~AcquireDiskSpace(){??}??void AcquireDiskSpace::slotDiskChanged( const QString& strDisk ){????double dTotalBytes, dFreeBytes;????GetDiskSpace( strDisk, dTotalBytes, dFreeBytes );????m_pEdtTotalSpace->setText( QString::number( dTotalBytes, 'f', 3 ) );????m_pEdtFreeSpace->setText( QString::number( dFreeBytes, 'f', 3 ) );}??void AcquireDiskSpace::GetDiskSpace( QString strDisk, double& dTotalBytes, double& dFreeBytes ){????LPCWSTR lpcwstrDriver = (LPCWSTR)strDisk.utf16();????ULARGE_INTEGER lFreeBytesAvailable, lTotalBytesTemp, lTotalFreeBytes;??????if( !GetDiskFreeSpaceEx( lpcwstrDriver, &lFreeBytesAvailable, &lTotalBytesTemp, &lTotalFreeBytes ) )????{????????QMessageBox::warning( 0, "Warning", "Acquire Disk Space Failed !" );????????dTotalBytes = -1;????????dFreeBytes = -1;????????return;????}??????//unit : GB????dTotalBytes = lTotalBytesTemp.QuadPart / 1024.0 / 1024 / 1024;????dFreeBytes = lTotalFreeBytes.QuadPart / 1024.0 / 1024 / 1024;}結(jié)果如下：
(1)C盤：
(2)D盤：
(3)F盤（F盤實際上并不存在，故獲取不到，給了默認(rèn)值-1,-1）
標(biāo)簽：
