浮点数被 C++ 四舍五入到小数点后一位

Question

我正在编写一个 C++ 程序，它接受用户输入并将其放入一个文件中。在这种情况下，它接受一个数字（例如 299.99），但是当使用双精度和浮点数 299.9...

时，C++ 将其四舍五入为 300（以前是双精度）

我的代码：

void Bank::deposit(){
std::cout << "You currently have " << getBalance() << " in your account.\nHow much would you like to deposit? Amount: ";
float amount = optionExists(amount);

if(amount < 1){
    std::cout << "Invalid Amount!" << std::endl;

    deposit();
}

float moneyInBank = getBalance();
setBalance(moneyInBank + amount);

std::cout << "Your balance of " << moneyInBank << " has been increased to " << getBalance() << std::endl;
std::string theLine = getUsername() + "," + getPassword() + "," + getAccountType() + "," + std::to_string(moneyInBank) + "," + std::to_string(getAdmin());
updateFile(theLine, getUsername(), getPassword(), getAccountType(), getBalance(), (getAdmin()));

displayMenu();
}

当我调用 getBalance() 方法时，它也是 returns 一个浮点数，但正如我所说，只有一位小数...

这是文本文件中的一个片段：

[name,password,type,BALANCE,admin]

lisa,mag24@773,C,24.99,0  ---> What I want (manually entered)

lols,23456,L,30,1  ---> What I got when using doubles

mark,passw0rd,S,24509.9,1  ---> What I got when using floats

额外说明：我使用 cmake 进行编译，使用 VSCode

进行编码

Answer 1

这 link 可能会有所帮助 [link][1]

float iBalance = getBalance(); 

std::cout<< std::setprecision(2)<<iBalance<< endl;

[1]: )%3B%20cout.

浮点数被 C++ 四舍五入到小数点后一位

floats getting rounded to 1 decimal by C++

c++

floating-point

double

rounding

text-files