在使用QNetworkAccessManager訪問網(wǎng)絡(luò)時，有時需要管理Cookie信息。Qt的QNetworkCookieJar類實現(xiàn)了一個簡單的Cookie容器，但它只在內(nèi)存中保留Cookie，該類的對象一旦被刪除，里面的cookies也被丟棄。如果想存儲在本地，必須繼承該類然后自己實現(xiàn)存儲。文檔中有這樣一段描述：

This class implements only the basic security recommended by the cookie specifications and does not implement any cookie acceptance policy (it accepts all cookies set by any requests). In order to override those rules, you should reimplement the cookiesForUrl() and setCookiesFromUrl() virtual functions. They are called by QNetworkReply and QNetworkAccessManager when they detect new cookies and when they require cookies.

See also QNetworkCookie, QNetworkAccessManager, QNetworkReply, QNetworkRequest, and QNetworkAccessManager::setCookieJar().

我這里簡單的實現(xiàn)了getCookies()和setCookies()功能。使用時生成一個NetworkCookieJar對象，再用void QNetworkAccessManager::setCookieJar(QNetworkCookieJar * cookieJar)設(shè)置一下即可。

// networkcookiejar.h
#ifndef NETWORKCOOKIEJAR_H
#define NETWORKCOOKIEJAR_H

#include <QNetworkCookie>
#include <QNetworkCookieJar>

class NetworkCookieJar : public QNetworkCookieJar
{
public:
    NetworkCookieJar();

    QList<QNetworkCookie> getCookies();
    void setCookies(const QList<QNetworkCookie>& cookieList);
};

#endif // NETWORKCOOKIEJAR_H

// networkcookiejar.cpp
#include "networkcookiejar.h"

NetworkCookieJar::NetworkCookieJar()
{
}

QList<QNetworkCookie> NetworkCookieJar::getCookies()
{
    return allCookies();
}

void NetworkCookieJar::setCookies(const QList<QNetworkCookie>& cookieList)
{
    if(this == NULL) {
        return;
    }
    setAllCookies(cookieList);
}