QT小项目-基于百度API的在线词典_qt 百度翻译api文档解读csdn

摘要：

基于百度api的在线词典是优衣酱结合百度API开发文档和网上教程JSON花了两天完成的，项目非常简陋，功能得益于百度翻译强大的翻译能力。现在发布到博客上，供大家交流学习。

项目演示：

说明：共包含两个界面：登录界面和翻译界面。

登录界面，需要输入appid和密匙，基于开发文档要求，要通过salt来获得签名，界面上salt一栏可以自定义输入0到2147483648任意的数值，也可以留空让程序自己生成32位二进制转十进制的随机数。

翻译界面，编辑发送区，点击翻译按钮，可以将翻译文本回显在接收区，默认中文转英文，可以自定义转换方式，但是必须遵照支持文档的要求来。

代码：

electronicdictionary.h

#ifndef ELECTRONICDICTIONARY_H
#define ELECTRONICDICTIONARY_H
 
#include <QWidget>
 
#include <QNetworkRequest>          //http网址管理类
#include <QNetworkReply>            //网页回复数据管理类
#include <QNetworkAccessManager>    //http请求方式管理类
 
namespace Ui {
class electronicDictionary;
}
 
class electronicDictionary : public QWidget
{
    Q_OBJECT
 
public:
    explicit electronicDictionary(QWidget *parent = 0,QString appid = "", QString key = "" , QString salt = "");
    ~electronicDictionary();
 
private slots:
    void on_teSend_textChanged();
 
    void on_pbTranslate_clicked();
 
    void httpReply(QNetworkReply *);
    void on_leFrom_editingFinished();
 
    void on_leTo_editingFinished();
 
    void on_pbSwitch_clicked();
 
private:
    Ui::electronicDictionary *ui;
 
    QString url;
 
    QString q;
    QString from;
    QString to;
 
    QString salt;
    QString sign;
    QString signMd5;
    QString appid;
    QString key;
 
    QNetworkRequest *request;
    QNetworkAccessManager *manager;
 
    QString networkReply;
 
    QJsonObject stringToJson(const QString jsonString);
    void md5Encryption();
    void urlEncode();
};
 
#endif // ELECTRONICDICTIONARY_H

widget.h

#ifndef WIDGET_H
#define WIDGET_H
 
#include <QWidget>
#include "electronicdictionary.h"
namespace Ui {
class Widget;
}
 
class Widget : public QWidget
{
    Q_OBJECT
 
public:
    explicit Widget(QWidget *parent = 0);
    ~Widget();
 
private slots:
    void on_leAppId_editingFinished();
    void on_leKey_editingFinished();
    void on_pbEncryption_clicked();
    void on_leSalt_editingFinished();
private:
    Ui::Widget *ui;
 
    QString salt;
    QString appid;
    QString key;
 
    electronicDictionary * dictionary;
};
 
#endif // WIDGET_H

electronicdictionary.cpp

#include "electronicdictionary.h"
#include "ui_electronicdictionary.h"
#include <QDebug>
#include <QJsonDocument>
#include <QJsonObject>
#include <QJsonParseError>
#include <QJsonArray>
#include <QVariant>
#include <QTextCodec>
electronicDictionary::electronicDictionary(QWidget *parent,QString appid, QString key, QString salt):
    QWidget(parent),
    ui(new Ui::electronicDictionary)
{
    ui->setupUi(this);
    //默认初始化
    from = "en";
    to = "zh";
    this->appid = appid;
    this->key = key;
    this->salt = salt;
}
 
electronicDictionary::~electronicDictionary()
{
    delete ui;
}
 
void electronicDictionary::on_teSend_textChanged()
{
    q = ui->teSend->toPlainText();
}
 
void electronicDictionary::on_pbTranslate_clicked()
{
    md5Encryption();
//    urlEncode();
    //设置访问地址
    url = "http://api.fanyi.baidu.com/api/trans/vip/translate?";
    url +=  "q=" + q +
            "&from=" + from +
            "&to=" + to +
            "&appid=" + appid +
            "&salt=" + salt +
            "&sign=" + signMd5;
    qDebug() << "url=" << url;
 
    //实例化网址管理
    request = new QNetworkRequest;
    //1、设置具体的网址
    request->setUrl(url);
    //2、实例化http请求方式
    manager = new QNetworkAccessManager;
    //关联信号 finished, 当网页回复数据时触发，此时才能在槽函数中，读取请求到的数据
    connect(manager, SIGNAL(finished(QNetworkReply*)), this, SLOT(httpReply(QNetworkReply *)));
    //3、get方法请求（get方法上传）
    manager->get(*request);
}
 
void electronicDictionary::httpReply(QNetworkReply * reply)
{
    networkReply = "";
    networkReply.append(reply->readAll());
    qDebug() << "networkReply" << networkReply;
 
    QJsonObject obj = stringToJson(networkReply);
    if(obj.contains("trans_result"))
    {
        QJsonValue val = obj.value("trans_result");
        if(val.isArray())
        {
            QJsonArray array = val.toArray();
            //            qDebug() << array;    //将该对象一次性打印出来
            qDebug() << array.at(0);
            if(array.at(0).isObject())
            {
                QJsonObject obj = array.at(0).toObject();
                if(obj.contains("dst"))
                {
                    QString utf8Reply = obj.value("dst").toString();
                    qDebug() << "utf8Reply" << utf8Reply;
                    ui->teRecv->clear();
                    ui->teRecv->insertPlainText(utf8Reply);
                }
            }
        }else{
            qDebug() << "错误:"<<val;
        }
    }
}
 
QJsonObject electronicDictionary::stringToJson(const QString jsonString)
{
    //QTextCodec类提供文本编码之间的转换
    //codecForName():搜索所有已安装的qtextcodec对象，并返回与名称最匹配的对象；
    //匹配是不区分大小写的。如果找不到与名称匹配的编解码器，则返回0。
    QTextCodec *tc = QTextCodec::codecForName("UTF-8");//防止中文乱码
    //指示编译器指定名称的参数不在函数正文中使用。这可用于抑制编译器警告，同时允许在其签名中使用有意义的参数名称定义函数。
    Q_UNUSED(tc);
 
    QJsonDocument jsonDocument = QJsonDocument::fromJson(jsonString.toUtf8());
    if (jsonDocument.isNull()){
        qDebug() << "数据解析有误"; //判断是否解析出问题
    }
    QJsonObject jsonObject = jsonDocument.object();
    //    qDebug() << "jsonObject" << jsonObject;
    return jsonObject;
}
 
void electronicDictionary::on_leFrom_editingFinished()
{
    from = ui->leFrom->text();
    qDebug() << "from=" << from;
}
 
void electronicDictionary::on_leTo_editingFinished()
{
    to = ui->leTo->text();
    qDebug() << "to=" << to;
}
 
void electronicDictionary::on_pbSwitch_clicked()
{
    QString tmp = from;
    from = to;
    to = tmp;
 
    ui->leFrom->setText(from);
    ui->leTo->setText(to);
    qDebug() << "from=" << from << ":to=" << to;
}
 
void electronicDictionary::md5Encryption()
{
    sign = appid+q+salt+key;
    qDebug() << "sign = " << sign;
    //md5加密
    //构造一个对象，该对象可根据指定method和之后添加的data，创建出加密散列。
    QCryptographicHash md(QCryptographicHash::Md5);
    md.addData(sign.toLatin1());
 
    signMd5 = "";
    //返回最后的散列值。
    //返回字节数组的十六进制编码副本。十六进制编码使用数字0-9和字母a-f。
    //将字节数组附加到此字符串。
    signMd5.append(md.result().toHex());
    ui->leMd5->setText(signMd5);
    qDebug() << "signMd5=" << signMd5;
}
 
void electronicDictionary::urlEncode()
{
    QTextCodec *tc = QTextCodec::codecForName("UTF-8");
    Q_UNUSED(tc);
    QByteArray byteArrayUTF8 = tc->fromUnicode(q);
    q.clear();
    q =  QString(byteArrayUTF8.toPercentEncoding());
    qDebug() << "URL encode q=" << q;
}
 
 

widget.cpp

#include "widget.h"
#include "ui_widget.h"
#include <QDebug>
#include <QRandomGenerator>
#include <QCryptographicHash>
Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);
}
 
Widget::~Widget()
{
    delete ui;
}
void Widget::on_leAppId_editingFinished()
{
    appid = ui->leAppId->text();
    qDebug() << "appid = " << appid;
}
 
void Widget::on_leKey_editingFinished()
{
    key = ui->leKey->text();
    qDebug() << "key = " << key;
}
 
void Widget::on_pbEncryption_clicked()
{
    if(salt.isEmpty())
    {
        quint32 randNumber = QRandomGenerator::global()->bounded(1073741825, 2147483648);
        //根据指定的基数返回与number相当的字符串
        salt = QString::number(randNumber,10);
        ui->leSalt->setText(salt);
        qDebug() << "randNumber=" << randNumber;
    }
    qDebug() << "salt=" << salt;
 
    dictionary = new electronicDictionary(0,appid,key,salt);
    dictionary->show();
    this->hide();
}
 
void Widget::on_leSalt_editingFinished()
{
    salt = ui->leSalt->text();
    qDebug() << "salt=" << salt;
}

main.cpp

#include "widget.h"
#include <QApplication>
 
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();
 
    return a.exec();
}

以上为整个项目粗略概述，有疑问或有意见、建议的恳请下方留言。

源码包地址：https://download.csdn.net/download/ezio_bel/11973260

优衣酱有时间再进行具体的阐述和改进，可能当作插叙放到下次博客中也可能放到下下次。