这个字符串比较不起作用

Question

所以当我输入我想要使用的月份，比如12月，并且我把722作为小时，程序就会说：“你输入的小时数不能超过月内的小时数720“。有没有办法解决？我不想每个月都做一些陈述，我觉得有一个更简单的方法。这也是我第一次上大学的程序

int userPackage, userHours; //Declaring integer variables 
double savings, savings2, total; //Declaring double value 
string userMonth; 
cout<<"\tHello.\nEnter the number of the package you have\n1) Package A\n2) Package B\n3) Package C\n"; //Prompts the user for their package in a menu like fashion 
cin>>userPackage; //gets package 
if(userPackage > 3 || userPackage < 1) //Error output for numbers that don't match packages 
{ 
    cout<<"Error, invalid choice"; 
    return 0; 
} 

cout<<"Enter the number of hours you have been online."; //Propmts the user for the number of hours they've been online 
cin>>userHours; //gets hours 
cout<<"Enter the month (by name): "; 
cin>>userMonth; 
cout<<"\n"; 
if(userMonth == "January","March","May","July","August","October","December") 
{ 
    if (userHours > 744) 
    { 
     cout<<"The amount of hours you entered cannot exceed the amount of hours within the month 744"; 
     return 0; 
    } 
} 
if(userMonth == "April", "June", "September", "November"); 
{ 
    if(userHours > 720) 
    { 
     cout<<"The amount of hours you entered cannot exceed the amount of hours within the month 720"; 
     return 0; 
    } 
} 
if(userMonth == "February"); 
{ 
    if (userHours > 672) 
    { 
     cout<<"The amount of hours you entered cannot exceed the amount of hours within the month 672"; 
     return 0; 
    } 
} 

Answer 1

if(userMonth == "January","March","May","July","August","October","December")

这不会做你认为它（即，它不比较userMonth到每个字符串。该您可能打算编写的声明（它假定您也想使用else if，即使您的代码没有）：

if (userMonth == "January" || 
    userMonth == "March" || 
    userMonth == "July" || 
    userMonth == "August" || 
    userMonth == "October" || 
    userMonth == "December") 
{ 
    ... 
} 
else if (userMonth == "April" || 
    userMonth == "June" || 
    userMonth == "September" || 
    userMonth == "November") 
{ 
} 
else if (userMonth == "February") 
{ 
} 

注：这些也是区分大小写的比较（即“1月”不等同于“1月”或其他任何差异），并且可能会更好地将所有内容转换为全部较低或全部大写。

if(userMonth == "April", "June", "September", "November");
// problematic trailing semi-colon ^

这结束if语句和无条件地执行下一个块。因此，当输入722时，它是总是大于720并且您收到您看到的消息。

在“February”的if逻辑中也有同样的错误。