c++ std::getline()函数的用法
时间: 2023-12-15 12:03:30 浏览: 525
`std::getline()` 是 C++ 标准库中的一个函数,用于从给定的输入流中读取一行数据。
其函数原型如下:
```c++
std::istream& getline(std::istream& is, std::string& str, char delim);
```
其中:
- `is`:输入流对象
- `str`:存储读取数据的字符串对象
- `delim`:指定分隔符,可选参数,默认为 `'\n'`
该函数会从输入流中读取字符,直到遇到指定分隔符或者文件结束符,然后将读取的字符存储到 `str` 中,并且不包括分隔符。如果指定分隔符为文件结束符,则读取到文件结束位置。
函数返回输入流对象的引用,可以用于连续读取多个行数据。
示例代码:
```c++
#include <iostream>
#include <string>
int main() {
std::string line;
std::cout << "Please enter a line of text: ";
std::getline(std::cin, line);
std::cout << "You entered: " << line << std::endl;
return 0;
}
```
运行结果:
```
Please enter a line of text: Hello, world!
You entered: Hello, world!
```
相关问题
// 从文件中加载参赛队伍信息 void loadTeamsFromFile(vector<Team>& teams) { ifstream inFile("team.txt"); if (!inFile.is_open()) { cout << "无法打开team.txt文件!" << endl; return; } string line; while (getline(inFile, line)) { stringstream ss(line); Team team; if (ss >> team.id) { ss >> std::ws; getline(ss, team.name, '\t'); ss >> std::ws; getline(ss, team.school, '\t'); ss >> std::ws; getline(ss, team.category, '\t'); ss >> std::ws; getline(ss, team.players, '\t'); ss >> std::ws; getline(ss, team.coach); cout << "id: " << team.id << ", name: " << team.name << ", school: " << team.school << ", category: " << team.category << ", players: " << team.players << ", coach: " << team.coach << endl; teams.push_back(team); } else { cout << "无效行:" << line << endl; } } } 根据这段代码写出之后按学校查找的代码
以下是按学校查找的代码示例:
``` c++
// 按学校查找参赛队伍
void searchTeamsBySchool(const vector<Team>& teams, const string& school) {
vector<Team> result; // 保存查找结果
for (const auto& team : teams) {
if (team.school == school) {
result.push_back(team);
}
}
if (result.empty()) {
cout << "没有找到 " << school << " 的参赛队伍。" << endl;
}
else {
cout << school << " 的参赛队伍如下:" << endl;
for (const auto& team : result) {
cout << "id: " << team.id << ", name: " << team.name << ", school: " << team.school
<< ", category: " << team.category << ", players: " << team.players << ", coach: " << team.coach << endl;
}
}
}
```
你可以将该函数添加到原有代码中,并在需要查找时调用该函数。
std::string input; std::getline(std::cin, input);
`std::getline` 是 C++ 标准库中的一个函数,用于从标准输入流(如 `std::cin`)读取一行文本,直到遇到换行符为止。这与 `std::cin >> input` 不同,后者会在遇到第一个空格时停止读取,假设 `input` 是一个预期接收完整单词的变量。
下面是一个使用 `std::getline` 的示例,展示如何将用户的多行输入读取到 `std::string` 中:
```cpp
#include <iostream>
#include <string>
using namespace std;
int main() {
string longInput;
cout << "Enter multiple lines of text (hit Enter to stop):" << endl;
getline(cin, longInput);
cout << "You entered: " << longInput << endl;
return 0;
}
```
在这个例子中,用户可以连续输入多行文本,直到按下回车键结束输入。`getline` 会把输入的每一行保存到 `longInput` 变量中。
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