qt http 请求乱码

转换函数

QString str;

QString str = QString::fromUtf8(str.toLatin1());

*********************************
开始

.pro 添加 QT += network
.h 添加 

#include <QNetworkReply>

private slots: 

　　　　void replyFinished(QNetworkReply*);

.cpp 添加
初始执行

    QNetworkAccessManager *manager = new QNetworkAccessManager(this);

     connect(manager, SIGNAL(finished(QNetworkReply*)),

             this, SLOT(replyFinished(QNetworkReply*)));

     manager->get(QNetworkRequest(QUrl("http://127.0.0.1/")));
实现槽

void MainWindow::replyFinished(QNetworkReply* p){

    QByteArray a1 = p->readAll();

    QString str;

    str.prepend(a1);

    ui->plainTextEdit->appendHtml(QString::fromUtf8(str.toLatin1()));

}