QT profile class encapsulates

• Many desktop software in the open, there are other options to remember passwords, but also in the case of networking can not be read, this is because it is written in the local configuration information, first read the local configuration before each open information to load configuration, then in this case, a configuration can be encapsulated classes help us later reuse.

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• Look at the local configuration information about the structure of
  
  which is a Windows text is random local configuration information
  can be seen, the configuration of the main text structure [属性名]and 键=值way constitute
  and is basically .iniconstituted in the form of a suffix. Based on these basic information, we would be very easy to write our own configuration text class
  followed by the actual code

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Header section:

#include <QFile>
#include <QString>
#include <QDebug>
#include <QMutex>

// 配置文件类
class QIniConfig{
public:
    QIniConfig();
    ~QIniConfig();

    static QIniConfig* GetInstance();
    bool Init(QString file_name);
    bool ConfigAttributeName(QString attr_name); //配置属性名
    bool WriteToConfig(QString key_,QString val_); //写入配置文件
    bool IsConfigAttributeName();//判断是否有[];从而判断是否已经设置配置属性名
    QString ReadValue(QString key_,QString attr_=""); //读取key的值 //没找到则返回""
    bool IsConfigStr(QString str_); // 判断是否为配置字符
    QString GetConfigName(QString str_); //从配置名格式中获取属性名[ii] 获取ii
private:
    bool m_b_init_file; // 是否初始化文件
    QFile* m_ini_file; //配置文件的句柄
    bool m_b_ConfigName; //是否配置属性名
    static QIniConfig* m_iniConfig;
    QString m_filename; //配置文件名：
};

• Implementation code:

#include "QIniConfig.h"

QIniConfig::QIniConfig():m_b_init_file(false),m_ini_file(nullptr),m_b_ConfigName(false),m_filename("")
{
    qDebug() << "Init Config";
}

QIniConfig* QIniConfig::m_iniConfig = nullptr;

QIniConfig* QIniConfig::GetInstance()
{
    if(!m_iniConfig)
    {
        m_iniConfig = new QIniConfig();
        return m_iniConfig;
    }
    return m_iniConfig;
}

QIniConfig::~QIniConfig()
{
   qDebug() << "Destroy Config";
   if(m_ini_file)
   {
       m_ini_file->close();
       delete m_ini_file;
       m_ini_file = nullptr;
   }
}

bool QIniConfig::Init(QString file_name)
{
    if(file_name.size()<1)
    {
        return false;
    }
    m_ini_file = new QFile(file_name);
    if(m_ini_file)
    {
        m_filename = file_name;
        m_b_init_file = true; // 说明初始化成功
        m_ini_file->open(QIODevice::ReadWrite|QIODevice::Append); //支持读写操作:往后写
        IsConfigAttributeName();
        return true;
    }
    return false;
}

// 配置属性名 [attributeName]形式
bool QIniConfig::ConfigAttributeName(QString attr_name)
{
    if(attr_name.size()<1)
    {
        return false;
    }
    if(!m_ini_file)
    {
        return false;
    }
    QString str_attribute = "[" + attr_name + "]" +"\n"; // 需要添加换行符，方便读取
    m_ini_file->write(str_attribute.toUtf8());
    m_b_ConfigName = true; //配置属性名成功
    return true;
}

bool QIniConfig::WriteToConfig(QString key_, QString val_)
{
    if(!m_ini_file)
    {
       return false;
    }
    if(!m_b_ConfigName)
    {
        return false;
    }
    QString str_key_val = key_ +"="+val_+"\n";
    m_ini_file->write(str_key_val.toUtf8());//写入
    return true;
}

bool QIniConfig::IsConfigAttributeName()
{
    QFile file_(m_filename);
    file_.open(QIODevice::ReadOnly);
    // 读取第一行即可[];//主要判断是否有[]
     QByteArray line = file_.readLine();
     QString str(line);
      qDebug() <<  str;
     if(str.size() < 1)
     {
         m_b_ConfigName = false;
     }
     else{
        if(str[0]=="[" && str[str.size()-2] == "]")
        {
            m_b_ConfigName = true;
        }
     }
    file_.close();
    return m_b_ConfigName;
}

QString QIniConfig::ReadValue(QString key_, QString attr_)
{
    QFile file_(m_filename);
    file_.open(QIODevice::ReadOnly);
    bool b_Found_Once = false;
    if(attr_ == "")
    {
        //等于空的情况，比较好处理，直接按行搜索即可
        while(!file_.atEnd())
        {
            QByteArray array_ = file_.readLine();
            QString str_(array_);
            if(str_.contains("="))
            {
                // 进行判断处理
                 str_.chop(1);//去掉空格
                 QStringList str_list = str_.split("=");
                 if(str_list[0] == key_)
                 {
                     qDebug() << "value is " << str_list[1];
                     file_.close();
                     return str_list[1];
                 }
            }
        }
        file_.close();
        return "";
    }
    else{
        while(!file_.atEnd())
        {

            QByteArray array_ = file_.readLine();
            QString str_(array_);
            // 此处为属性名
            if(IsConfigStr(str_))
            {
              if(b_Found_Once)
              {
                  file_.close();
                  return "";
              }
              QString str_configs =  GetConfigName(str_);
              if(str_configs == attr_)
              {
                  b_Found_Once = true;
                  qDebug() << "find";
              }
            }
            // 此处为key = value形式
            if(b_Found_Once)
            {
                if(str_.contains("="))
                {
                    // 进行判断处理
                     str_.chop(1);//去掉空格
                     QStringList str_list = str_.split("=");
                     if(str_list[0] == key_)
                     {
                          qDebug() << "value is " << str_list[1];
                         file_.close();
                         return str_list[1];
                     }
                }
            }
        }

        file_.close();
        return "";
    }
    file_.close();
    return "";

}

bool QIniConfig::IsConfigStr(QString str_)
{
    if(str_.size() < 3)
    {
        return false;
    }
    if(str_[0]=="[" && str_[str_.size()-2] == "]")
    {
        return true;
    }
    return false;
}

QString QIniConfig::GetConfigName(QString str_)
{
    str_.chop(1);
    QString strss = str_.replace("[","");
    QString str_configName = strss.replace("]","");
    return str_configName;

}

• Since the code is basically a comment, so we can directly talk about its method calls

    // 初始化配置文件：{文件名}
    QIniConfig::GetInstance()->Init(ini_path);
    
    // 配置属性名部分
    QIniConfig::GetInstance()->ConfigAttributeName("test");
    //写入相关的配置信息
    QIniConfig::GetInstance()->WriteToConfig("keys","world");
    //读取值
    QString value_ = QIniConfig::GetInstance()->ReadValue("keys","test");

More convenient, read the value part there are two ways, one is global reading, that is not based on the attribute name is read, and the other is based on the way the property name read , for the corresponding scene we can use flexible call .