std::string转换为数值
时间: 2024-09-28 13:17:25 浏览: 28
在C++中,你可以使用`std::stoi()`函数将`std::string`类型的字符串转换为整数(int),如果需要转换为长整型(long)可以使用`std::stol()`,如果是浮点数(float)则可以使用`std::stof()`或`std::stod()`。例如:
```cpp
#include <iostream>
#include <string>
int main() {
std::string str_number = "123";
int int_number = std::stoi(str_number); // 转换为int
long long_number = std::stol(str_number); // 转换为long long
double float_number = std::stod(str_number); // 转换为float
// 确保输入的是有效数字,否则会抛出异常
if (std::cin >> str_number && !str_number.empty()) {
try {
int_number = std::stoi(str_number);
float_number = std::stod(str_number);
} catch (...) {
std::cout << "Invalid number format!" << std::endl;
}
}
return 0;
}
```
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