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c++ - 试图从txt文件中读取两条数据并输出[C++]

问题描述

txt 文件 

class calcBMI {
    public:
        string line;
        string line2;
        fstream search;
        short loop = 0;
        string weight[6];
        string height[6];
        int index[6] = { 1, 2, 3, 4, 5 };
        int i;

        void getHeight();
        void getWeight();

    };

.

void calcBMI::getWeight() {

    search.open("name.txt"); //Opens the text file in which the user details are stored
    if (search.is_open())
    {
        while (getline(search, line) && (getline(search, line2))) { //While the program searches for the lines in the text file
            if (line.find("Current Weight(KG): ") != string::npos && (line2.find("Height(Metres)") != string::npos)) { //If the string "Name" isnt the last word on the line
                weight[loop] = line; //Assings the strings read from the text file to the array called weight
                height[loop] = line2;
                cout << index[loop] << ". " << weight[loop] << ", " << height[loop] << endl; //Outputs the index array which loops through the numbers in the array and outputs the weight variable which loops through the strings in the array
                loop++; //Iterates the loop 

            }

        }

    }

}

所以我试图从一个包含 5 个用户的 txt 文件中读取两条数据。存储的有关用户的数据是他们的姓名、身高、体重和以前的体重。文件的布局/格式如下。

我正在尝试使用以下代码读取用户的身高和体重，但是当我运行代码时，程序不输出任何内容。

该程序应打印：

  1. 当前身高（KG）：00，身高（米）：00
  2. 当前身高（KG）：00，身高（米）：00
  3. 当前身高（KG）：00，身高（米）：00
  4. 当前身高（KG）：00，身高（米）：00
  5. 当前身高（KG）：00，身高（米）：00

但是，它什么也不打印。

标签： c++loopsfstreamgetline

解决方案

这是一个重写的版本：

        bool w = false, h = false;
        while (getline(search, line))
        {
            if (line.find("Current Weight(KG):") != string::npos)
            {
                weight[loop] = line; //Assings the strings read from the text file to the array called weight
                w = true;
            }
            else if (line.find("Height(Metres)") != string::npos)
            {
                height[loop] = line;
                h = true;
            }

            if (w && h)
            {
                cout << index[loop] << ". " << weight[loop] << ", " << height[loop] << endl; //Outputs the index array which loops through the numbers in the array and outputs the weight variable which loops through the strings in the array
                loop++; //Iterates the loop 
                w = false;
                h = false;
            }
        }

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