读二进制文件和输出它的控制台窗口

void createtask(char filename[MAX]) 
{ 
char filenameb[MAX]; 
strcpy(filenameb,filename); 
strcat(filenameb,".dat"); 

fstream writeb; 
fstream readb; 

writeb.open(filenameb,ios::out | ios::binary); 

task t; 
int nooftask; 
cout<<"-----------------------------------" 
    <<endl 
    <<endl 
    <<"Creation of task" 
    <<endl 
    <<endl 
    <<"How many task ?: "; 
cin>>nooftask; 

cin.clear(); 
cin.ignore(200,'\n'); 

for(int i=1;i<=nooftask;i++) 
{ 
    t.task_no=i; 

    cout<<endl 
     <<"Information for task " 
     <<i 
     <<endl 
     <<endl; 


    cout<<"Title for assessment: "; 
    cin.getline(t.task_title,200); 


    cout<<"Weight (%): "; 
    cin>>t.task_weight; 

    cout<<"Full mark upon: "; 
    cin>>t.task_fullmark; 

    cin.clear(); 
    cin.ignore(200,'\n'); 

    cout<<"Description: "; 
    cin.getline(t.task_descrip,200); 

    writeb.write(reinterpret_cast <const char *>(&t), sizeof (t)); 

    cout<<t.task_descrip 
     <<endl 
     <<t.task_fullmark 
     <<endl 
     <<t.task_no; 


} 

writeb.clear(); 



writeb.close(); 

cout<<endl 
    <<endl 
    <<"The creation of task file is completed" 
    <<endl 
    <<endl 
    <<"The summary of creation" 
    <<endl 
    <<endl; 

//summarytask(readb,filenameb); 

    //start 
    cout<<"Summary of task" 
    <<endl 
    <<endl; 

    readb.open(filenameb,ios::binary | ios::in); 


while (readb.read(reinterpret_cast < char *>(&t), sizeof (t))); // problem is here 
{ 
    cout<<endl 
     <<endl 
     <<t.task_no // programme only output the last record in binary file 
     <<endl 
     <<t.task_title;// 

} 

readb.close(); 
//end 


}

一切正常，只是我不能似乎能够输出二进制文件，控制台窗口中的所有记录。由于某种原因，我只能输出二进制文件中的最后一条记录，谢谢读二进制文件和输出它的控制台窗口

来源

2013-01-14 Computernerd

您是否检查过二进制文件的内容？它可能只填写最后一条记录。读取和写入都看起来正确。 – ipinak

我认为在写完之前，你必须冲洗你的流。 – ipinak

我加了;

while (readb.read(reinterpret_cast < char *>(&t), sizeof (t))); // there shouldnt 
//be a ; after the while

来源

2013-01-14 11:48:52 Computernerd

读二进制文件和输出它的控制台窗口

回答

相关问题