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有个关于文件输入/输出的有关问题

发布时间: 2012-02-06 15:52:45 作者: rapoo

有个关于文件输入/输出的问题
输出文件的例子运行以后当前文件夹没有生成文件
输入文件的例子运行以后找不到指定的文件,真是晕了
输出:
#include <iostream>
#include <fstream> // for file I/O

int main()
{
using namespace std;

char automobile[50];
int year;
double a_price;
double d_price;

ofstream outFile; // create object for output
outFile.open( "carinfo.txt "); // associate with a file

cout < < "Enter the make and model of automobile: ";
cin.getline(automobile, 50);
cout < < "Enter the model year: ";
cin > > year;
cout < < "Enter the original asking price: ";
cin > > a_price;
d_price = 0.913 * a_price;

// display information on screen with cout

cout < < fixed;
cout.precision(2);
cout.setf(ios_base::showpoint);
cout < < "Make and model: " < < automobile < < endl;
cout < < "Year: " < < year < < endl;
cout < < "Was asking $ " < < a_price < < endl;
cout < < "Now asking $ " < < d_price < < endl;

// now do exact same things using outFile instead of cout

outFile < < fixed;
outFile.precision(2);
outFile.setf(ios_base::showpoint);
outFile < < "Make and model: " < < automobile < < endl;
outFile < < "Year: " < < year < < endl;
outFile < < "Was asking $ " < < a_price < < endl;
outFile < < "Now asking $ " < < d_price < < endl;

outFile.close(); // done with file


return 0;
}
输入:
#include <iostream>
#include <fstream> // file I/O suppport
#include <cstdlib> // support for exit()
const int SIZE = 60;
int main()
{
using namespace std;
char filename[SIZE];
ifstream inFile; // object for handling file input

cout < < "Enter name of data file: ";
cin.getline(filename, SIZE);
inFile.open(filename); // associate inFile with a file
if (!inFile.is_open()) // failed to open file
{
cout < < "Could not open the file " < < filename < < endl;
cout < < "Program terminating.\n ";
exit(EXIT_FAILURE);
}
double value;
double sum = 0.0;
int count = 0; // number of items read

inFile > > value; // get first value
while (inFile.good()) // while input good and not at EOF
{
++count; // one more item read
sum += value; // calculate running total
inFile > > value; // get next value
}
if (inFile.eof())
cout < < "End of file reached.\n ";
else if (inFile.fail())
cout < < "Input terminated by data mismatch.\n ";
else
cout < < "Input terminated for unknown reason.\n ";
if (count == 0)


cout < < "No data processed.\n ";
else
{
cout < < "Items read: " < < count < < endl;
cout < < "Sum: " < < sum < < endl;
cout < < "Average: " < < sum / count < < endl;
}
inFile.close(); // finished with the file
return 0;
}
我的编译器是DEV-CPP,请大家帮忙看下是哪里的问题?


[解决办法]
输出:
outFile.open( "d:\\carinfo.txt ");//指定下路径

输入时也一样
你输入的时候要把路径指定好

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