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C++ Reading file

In file handling, read() function is used to read data from the file into the program. The read() uses ifstream library to read data from a file.

Syntax

file-stream-class   file-stream-object;  
file-stream-object.read((char *)&var , sizeof (var));

<h3">Example

ofstream  outfile;        
outfile . read((char*)&emp,sizeof(emp));

C++ File Handling read() Function Example

Reading the content of existing file 'employee.txt'.

#include <iostream>  
#include <fstream>  
using namespace std;  
class employee  
{  
    private:  
        char name[30];  
        float salary;  
    public:  
        void showData(void)  
        {  
        cout<<"Name:"<<name<<endl;  
        cout<<"Salary:"<<salary<<endl;  
        }  
};  
int main()  
{  
    employee emp;  
    //open file in input mode and read data  
    ifstream file;  
    file.open("employee.txt",ios::in);  
    if(!file){  
        cout<<"Error in opening file.";  
        return 0;  
    }  
    //read data from file  
    file.read((char*)&emp,sizeof(emp));  
    emp.showData();  
    file.close();        
    return 0;  
}

Output: 


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