qt把自定义类输入到二进制文件中，从二进制文件中读取类

// mlist.h文件

#ifndef MLIST_H

#define MLIST_H

#include

#include

#include

using namespace std;

template<class T>

struct List

{

    T data;

    List<T> *next;

};

template<class T>

class MList

{

private:

    List<T> *root;

    int len;//长度

    void deleteAll()

    {

        List<T> *p=root;

        if(p==NULL){delete p;return;}

        else {

            do{

                root=root->next;

                delete p;

                p=root;

            }while(root);

        }

    }

public:

    MList(){

        root=NULL;

        this->len=0;

    }

//    MList(MList &other){}

    ~MList(){deleteAll();}

    List<T> *createNewList(const T &val){

        List<T> *p=new List<T>;

        p->data=val;

        p->next=NULL;

        return p;}

    int length()const//不改变内容

    {

        return len;

    }

    int size()const{return len;}

    void append(const T &val){

        if(this->root==NULL){this->root=createNewList(val);}

        else {

           List<T> *p=root;

           while(p->next)

           {

               p=p->next;

           }

           p->next=createNewList(val);

        }

        len++;

    }

    void prepend(const T &val)

    {

        if(this->root==NULL)

            this->root=createNewList(val);

        else

        {

           List<T> *p=createNewList(val);

           p->next=root;

           root=p;

        }

        this->len=this->len+1;

    }

    const T& at(int index)const

    {

        if((index<0)||(index+1>length()))throw "index的大小应>0小于length()";

        else

        {

            List<T> *p=this->root;

            for(int i=0;i 
  
            {
 
  
                p=p->next;
 
  
            }
 
  
            return p->data;
 
  
        }
 
  
    }
 
  
    void removeAt(int index)
 
  
    {
 
  
        if((index>len-1)||index<0)return;
 
  
        else if(index==0) {removeFirst();return;}
 
  
        else if(index==len) {removeLast();return;}
 
  
        {
 
  
            List<T> *p=root;
 
  
            for(int i=0;i1;i++)//找到该节点的前一个
 
  
            {
 
  
                p=p->next;
 
  
            }
 
  
 
  
            List<T> *p_=p->next->next;
 
  
            delete p->next;
 
  
            p->next=p_;
 
  
            len--;
 
  
        }
 
  
    }
 
  
 
  
    void remove(int from,int to)
 
  
    {
 
  
        if(from>to)return;
 
  
        if(from<0)return;
 
  
        if(to>len)return;
 
  
        for(int i=to-from+1;i>0;i--)
 
  
        {
 
  
            removeAt(from);
 
  
        }
 
  
    }
 
  
 
  
    void removeFirst()
 
  
    {
 
  
        if(len==0)return;
 
  
        List<T> *p=root;
 
  
        root=root->next;
 
  
        delete p;
 
  
        len--;
 
  
    }
 
  
 
  
    void removeLast()
 
  
    {
 
  
        if(len==0)return;
 
  
        if(len==1){delete root;root=NULL;len--;return;}
 
  
        List<T> *p=root;
 
  
        while(p->next->next)
 
  
        {
 
  
            p=p->next;
 
  
        }
 
  
        List<T> *p_=p->next;
 
  
        delete p->next;
 
  
        p_->next=NULL;
 
  
        len--;
 
  
    }
 
  
 
  
    void replace(int index,T &val)
 
  
    {
 
  
        if((index>len-1)||(index<0))return;
 
  
        else
 
  
        {
 
  
            List<T> *p=root;
 
  
            for(int i=0;i 
  
            {
 
  
                p=p->next;
 
  
            }
 
  
            p->data=val;
 
  
        }
 
  
    }
 
  
    int count(const T &val)const{
 
  
        int sum=0;
 
  
        List<T> *p=root;
 
  
        while(p)
 
  
        {
 
  
            if(p->data==val)sum++;
 
  
            p=p->next;
 
  
        }
 
  
        return sum;
 
  
    }
 
  
 
  
    /*写入到二进制文件*/
 
  
    void writeBinaryFile(QString &binaryFilename){
 
  
        QFile file(binaryFilename);
 
  
        if(!file.exists())return;
 
  
        file.open(QIODevice::WriteOnly);
 
  
        List<T> *p=root;
 
  
        while(p)
 
  
        {
 
  
            file.write((char*)(&(p->data)),sizeof(T));
 
  
            p=p->next;
 
  
        }
 
  
        file.close();
 
  
    }
 
  
    /*从二进制文件中读取*/
 
  
    void readBinaryFile(QString &binaryFilename){
 
  
        QFile file(binaryFilename);
 
  
        if(!file.exists())return;
 
  
        file.open(QIODevice::ReadOnly);
 
  
       while(1){
 
  
           T p;
 
  
            file.read((char*)&p,sizeof(T));
 
  
            if((p)==T()){file.close();return;}
 
  
            append(p);
 
  
        }
 
  
 
  
 
  
 
  
//        file.read();
 
  
 
  
        file.close();
 
  
    }
 
  
 
  
    //    ~MList();
 
  
};
 
  
 
  
#endif // MLIST_H
 
  

 
  

 
  

 
  
 
  
#ifndef STUDENT_H
 
  
#define STUDENT_H
 
  
 
  
#include
 
  
 
  
//class MList;
 
  
//class List;
 
  
#include"mlist.h"
 
  
 
  
using namespace std;
 
  
struct Student
 
  
{
 
  
    QString name;
 
  
    int age;
 
  
    Student(){name="";age=-1;}
 
  
    bool operator !=(const Student &val){if((val.age==age)&&(val.name==name))return false;else return true;}
 
  
    bool operator ==(const Student &val){if((val.age==age)&&(val.name==name))return true;else return false;}
 
  
};
 
  
typedef MList<Student> StudentList;
 
  
 
  
#endif // STUDENT_H
 
  
 
  
// 主函数
 
  
#include"mlist.h"
 
  
#include"stuent.h"
 
  
 
  
int main(int argc, char *argv[])
 
  
{
 
  
    QApplication a(argc, argv);
 
  
//    readWrite();
 
  
 
  
    StudentList list,list1;/*typedef MList<Student> StudentList;*/
 
  
    Student stu1,stu2,stu3;
 
  
    stu1.name="wang";
 
  
    stu2.name="hujingtao";
 
  
    stu3.name="xijinping";
 
  
    stu1.age=20;
 
  
    stu2.age=54;
 
  
    stu3.age=55;
 
  
    list.append(stu1);
 
  
    list.append(stu2);
 
  
    list.append(stu3);
 
  
    QString filename("studentlist.dat");
 
  
    list.writeBinaryFile(filename);
 
  
    list1.readBinaryFile(filename);
 
  
    for(int i=0;i 
  
    {
 
  
        qDebug()<name<age< 
  
    }
 
  
//    MainWindow w;
 
  
//    w.show();
 
  
//    StudentSizeList list;
 
  
//    list.
 
  
    return a.exec();
 
  
}