Question

我的作业要求我打开一个文件，但是如果没有打开，则会进行3次尝试，但是当我在第二次和第三次尝试中输入正确的文件时，仍然会出现错误，我写了'ERROR：File “ << input_filename <<“无法打开以供输入”'，并转到我的else语句

char input_filename [90]; ifstream输入；

cout << "Type the name of the input file which will hold the simulation results : " << endl;
cin>> input_filename;
input.open(input_filename);
if (input.fail())//if the file doesn't open it will go to the do while loop error message
{   

    int i = 0;
    int h = 0;
     do
    {   
        cout << "ERROR: File " << input_filename << " could not be opened for input" << endl;

        cin >> input_filename;// allows user to reinput filename
        input.open(input_filename);//opens file 
        if ( !input.fail()) 
        {   
            cout << "if statement" << endl;
            h++;// if h doesn't equal 1 it goes out of the loop
        }
            else
            {   
            cout << "else statement" << endl;
                i++;//post-decrement allows for 2 more tries to input file
            }
        if (i >= 2) 
        {
            cout << "ERROR: You exceeded maximum number of tries allowed" << endl;
            cout << "while entering the input file name" << endl;
            return 1;// return 1 represents the error of the input not opening after the 3rd time of inputing
        }
     } while (i < 2 && h != 0);// do while because it need to be a post condition for two varibles


}

Answer 1

如果到达第106行，则表明文件输入成功。在那一行，您不应该增加h。实际上，如果您想跳出循环，则应将h保留为零（假设文件输入有效）。

我打开文件后，为什么我的代码跳过if语句并转到else

1 个答案: