C++ 输入验证以仅接受数字

我正在创建一个程序，它应该只允许接受数字，如果输入了一个字母，它应该重新要求用户输入一个数字。当我运行代码时，我得到一个错误，说中断有问题。这是我的代码副本

#include <iostream>
using namespace std;

class Triangle
{
    private:
        double base;
        double height;
    public:
        void setBase(double);
        void setHeight(double);
        double getBase() const;
        double getHeight() const;
        double getArea() const;
};

void Triangle::setBase(double b)
{
    base = b;
}

void Triangle::setHeight(double hg)
{
    height = hg;
}

double Triangle::getBase() const
{
    return base;
}

ouble Triangle::getHeight() const
{
    return height;
}

double Triangle::getArea() const
{
    return .50 *(base * height);
}

int main()
{
    double number; 
    double totalArea;
    Triangle one; 
    Triangle two;
    Triangle three;

    do
    {
        cout << "What is the base of Triangle One:"; 
        cin >> number;

        one.setBase(number); 
            cout << "You have entered " << number << " for the base of the triangle.\n";

        cout << "What is the height of Triangle One:"; 
        cin >> number;
        one.setHeight(number); 
            cout << "You have entered " << number << " for the height of the triangle.\n";

            cout << "What is the base of Triangle Two: "; 
        cin >> number;
        two.setBase(number); 
            cout << "You have entered " << number << " for the base of the triangle.\n";

        cout << "What is the height of Triangle Two:"; 
        cin >> number;
        two.setHeight(number); 
            cout << "You have entered " << number << " for the height of the triangle.\n";

            cout << "What is the base of Triangle Three:"; 
        cin >> number;
        three.setBase(number); 
            cout << "You have entered " << number << " for the base of the triangle.\n";

        cout << "What is the height of Triangle Three:"; 
        cin >> number;
        three.setHeight(number); 
             cout << "You have entered " << number << " for the height of the triangle.\n";
    }   
    while (0); 
    {
        if (cin >> number) 
        {
            break;
        } 
        else 
        {
            cout << "Invalid Input! Please input a numerical value." << endl;
                    cin.clear();
            while (cin.get() != '\n') ; 
        }
    }


    totalArea = one.getArea() + two.getArea() + three.getArea(); 

    cout << "The total area of the three triangles is " << totalArea << endl; 

    return 0; 

}

#包括
使用名称空间std；
阶级三角
{
私人：
双基；
双高；
公众：
无效挫折（双）；
空隙设置高度（双倍）；
双getBase（）常量；
双getHeight（）常量；
双getArea（）常量；
};
空心三角形：：收进（双b）
{
基数=b；
}
空心三角形：：设置高度（双汞柱）
{
高度=汞柱；
}
双三角形：：getBase（）常量
{
返回基地；
}
双三角形：：getHeight（）常量
{
返回高度；
}
双三角形：：getArea（）常量
{
返回.50*（基准*高度）；
}
int main（）
{
双数；
双总面积；
三角形一；
三角形二；
三角形三；
做
{
数量；
一、挫折（数）；
cout您在双on中缺少d：

ouble Triangle::getHeight() const
{
    return height;
}

执行while语法应如下所示：

do{

}while(x == 0);

do{

}while();
{ <--- //this

} <--- //and this

#include <iostream>
#include <stdexcept>
#include <string>
using namespace std;

//Work-Class 
class Triangle {
private:
    double base;
    double height;

public:
    void setBase(double);
    void setHeight(double);
    double getBase() const;
    double getHeight() const;
    double getArea() const;
};

void Triangle::setBase(double b) {
    base = b;
}

void Triangle::setHeight(double hg) {
    height = hg;
}

double Triangle::getBase()const {
    return base;
}

double Triangle::getHeight() const {
    return height;
}

double Triangle::getArea() const {
    return (base*height) / 2;
}

//conversion and test function
double getDoubleString(string questString) {
    string userAnswer;
    double d;

    cout << questString;
    getline(cin, userAnswer);
    try {
        d = stod(userAnswer);
    }
    catch (const std::invalid_argument& ia) {
        cerr << "Invalid argument: " << ia.what() << '\n';
        d = 0.0;
    }
    return d;
}

//Enter the hell
int main() {
    double number;
    double totalArea;
    Triangle one;
    Triangle two;
    Triangle three;

    cout << "--------------------------------------------------------------\n\n";
    //Triangle one
    one.setBase(getDoubleString("What is the base of Triangle One: "));
    cout << "You have entered " << one.getBase() << " for the base of the triangle.\n";
    one.setHeight(getDoubleString("What is the height of Triangle One: "));
    cout << "You have entered " << one.getHeight() << " for the height of the triangle.\n\n";

    //Triangle two
    two.setBase(getDoubleString("What is the base of Triangle Two: "));
    cout << "You have entered " << two.getBase() << " for the base of the triangle.\n";
    two.setHeight(getDoubleString("What is the height of Triangle Two: "));
    cout << "You have entered " << two.getHeight() << " for the height of the triangle.\n\n";

    //Triangle three
    three.setBase(getDoubleString("What is the base of Triangle Three: "));
    cout << "You have entered " << three.getBase() << " for the base of the triangle.\n";
    three.setHeight(getDoubleString("What is the height of Triangle Three: "));
    cout << "You have entered " << three.getHeight() << " for the height of the triangle.\n\n";

    totalArea = one.getArea() + two.getArea() + three.getArea();

    cout << "--------------------------------------------------------------\n\n";
    cout << "The total area of the three triangles ist " << totalArea << endl;
    return 0;
}

你是怎么做到的

do{

}while(x == 0);

do{

}while();
{ <--- //this

} <--- //and this

#include <iostream>
#include <stdexcept>
#include <string>
using namespace std;

//Work-Class 
class Triangle {
private:
    double base;
    double height;

public:
    void setBase(double);
    void setHeight(double);
    double getBase() const;
    double getHeight() const;
    double getArea() const;
};

void Triangle::setBase(double b) {
    base = b;
}

void Triangle::setHeight(double hg) {
    height = hg;
}

double Triangle::getBase()const {
    return base;
}

double Triangle::getHeight() const {
    return height;
}

double Triangle::getArea() const {
    return (base*height) / 2;
}

//conversion and test function
double getDoubleString(string questString) {
    string userAnswer;
    double d;

    cout << questString;
    getline(cin, userAnswer);
    try {
        d = stod(userAnswer);
    }
    catch (const std::invalid_argument& ia) {
        cerr << "Invalid argument: " << ia.what() << '\n';
        d = 0.0;
    }
    return d;
}

//Enter the hell
int main() {
    double number;
    double totalArea;
    Triangle one;
    Triangle two;
    Triangle three;

    cout << "--------------------------------------------------------------\n\n";
    //Triangle one
    one.setBase(getDoubleString("What is the base of Triangle One: "));
    cout << "You have entered " << one.getBase() << " for the base of the triangle.\n";
    one.setHeight(getDoubleString("What is the height of Triangle One: "));
    cout << "You have entered " << one.getHeight() << " for the height of the triangle.\n\n";

    //Triangle two
    two.setBase(getDoubleString("What is the base of Triangle Two: "));
    cout << "You have entered " << two.getBase() << " for the base of the triangle.\n";
    two.setHeight(getDoubleString("What is the height of Triangle Two: "));
    cout << "You have entered " << two.getHeight() << " for the height of the triangle.\n\n";

    //Triangle three
    three.setBase(getDoubleString("What is the base of Triangle Three: "));
    cout << "You have entered " << three.getBase() << " for the base of the triangle.\n";
    three.setHeight(getDoubleString("What is the height of Triangle Three: "));
    cout << "You have entered " << three.getHeight() << " for the height of the triangle.\n\n";

    totalArea = one.getArea() + two.getArea() + three.getArea();

    cout << "--------------------------------------------------------------\n\n";
    cout << "The total area of the three triangles ist " << totalArea << endl;
    return 0;
}

do{
}while（）；
{ 
做{
...
}而（0）
意味着您的循环只执行一次。它将始终退出。因此，您可以将此do while循环保留下来

while（0）之后的代码；看起来像是测试用户输入的函数
我将介绍字符串和异常，并这样编写：

do{

}while(x == 0);

do{

}while();
{ <--- //this

} <--- //and this

#include <iostream>
#include <stdexcept>
#include <string>
using namespace std;

//Work-Class 
class Triangle {
private:
    double base;
    double height;

public:
    void setBase(double);
    void setHeight(double);
    double getBase() const;
    double getHeight() const;
    double getArea() const;
};

void Triangle::setBase(double b) {
    base = b;
}

void Triangle::setHeight(double hg) {
    height = hg;
}

double Triangle::getBase()const {
    return base;
}

double Triangle::getHeight() const {
    return height;
}

double Triangle::getArea() const {
    return (base*height) / 2;
}

//conversion and test function
double getDoubleString(string questString) {
    string userAnswer;
    double d;

    cout << questString;
    getline(cin, userAnswer);
    try {
        d = stod(userAnswer);
    }
    catch (const std::invalid_argument& ia) {
        cerr << "Invalid argument: " << ia.what() << '\n';
        d = 0.0;
    }
    return d;
}

//Enter the hell
int main() {
    double number;
    double totalArea;
    Triangle one;
    Triangle two;
    Triangle three;

    cout << "--------------------------------------------------------------\n\n";
    //Triangle one
    one.setBase(getDoubleString("What is the base of Triangle One: "));
    cout << "You have entered " << one.getBase() << " for the base of the triangle.\n";
    one.setHeight(getDoubleString("What is the height of Triangle One: "));
    cout << "You have entered " << one.getHeight() << " for the height of the triangle.\n\n";

    //Triangle two
    two.setBase(getDoubleString("What is the base of Triangle Two: "));
    cout << "You have entered " << two.getBase() << " for the base of the triangle.\n";
    two.setHeight(getDoubleString("What is the height of Triangle Two: "));
    cout << "You have entered " << two.getHeight() << " for the height of the triangle.\n\n";

    //Triangle three
    three.setBase(getDoubleString("What is the base of Triangle Three: "));
    cout << "You have entered " << three.getBase() << " for the base of the triangle.\n";
    three.setHeight(getDoubleString("What is the height of Triangle Three: "));
    cout << "You have entered " << three.getHeight() << " for the height of the triangle.\n\n";

    totalArea = one.getArea() + two.getArea() + three.getArea();

    cout << "--------------------------------------------------------------\n\n";
    cout << "The total area of the three triangles ist " << totalArea << endl;
    return 0;
}

#包括
#包括
#包括
使用名称空间std；
//工人阶级
阶级三角{
私人：
双基；
双高；
公众：
无效挫折（双）；
空隙设置高度（双倍）；
双getBase（）常量；
双getHeight（）常量；
双getArea（）常量；
};
空心三角形：：收进（双b）{
基数=b；
}
空心三角形：：设置高度（双汞柱）{
高度=汞柱；
}
双三角形：：getBase（）常量{
返回基地；
}
双三角形：：getHeight（）常量{
返回高度；
}
双三角形：：getArea（）常量{
返回（基准*高度）/2；
}
//转换和测试功能
double getDoubleString（字符串questString）{
字符串userAnswer；
双d；
无法显示准确的错误消息。
while（0）；
不正确。请删除
；
。而且
0
被视为
false
，因此将永远不会进入此循环（即使您修复了
；
）@TatsuyukiIshi我已经添加了错误message@WhozCraig我将0改为1，并删除了；我仍然收到相同的errorObservant，但与问题无关。抱歉，这里的代码是如何输入的，但我有d@WhozCraig这确实与问题有关。海报的主要目的是不接收t中的错误继承人程序。虽然正确，但这不会纠正无需连接循环或开关的
中断问题。