字符串操作技巧分享：C++ tostring

在 C++ 中，std::to_string() 函數用于將數字類型（如 int、float、double 等）轉換為字符串

#include<iostream>
#include<string>

int main() {
    int num = 42;
    std::string str_num = std::to_string(num);

    std::cout << "The integer is: "<< num<< std::endl;
    std::cout << "The string representation of the integer is: "<< str_num<< std::endl;

    return 0;
}

輸出結果：

The integer is: 42
The string representation of the integer is: 42

std::to_string() 函數還可以用于其他數字類型，例如 float 和 double：

#include<iostream>
#include<string>

int main() {
    float num_float = 3.14f;
    std::string str_num_float = std::to_string(num_float);

    double num_double = 2.71828;
    std::string str_num_double = std::to_string(num_double);

    std::cout << "The float is: "<< num_float<< std::endl;
    std::cout << "The string representation of the float is: "<< str_num_float<< std::endl;
    std::cout << "The double is: "<< num_double<< std::endl;
    std::cout << "The string representation of the double is: "<< str_num_double<< std::endl;

    return 0;
}

輸出結果：

The float is: 3.14
The string representation of the float is: 3.14
The double is: 2.71828
The string representation of the double is: 2.71828

請注意，對于浮點數，std::to_string() 的精度可能與預期不同。如果需要更高的精度或格式控制，可以考慮使用 std::ostringstream 或 C++ 標準庫中的其他字符串格式化工具。