我的开关不工作

Question

case 1: //Option 1
    {
        cout<<"Enter Car Brand:"<<endl;
        cin>>search_car; //Identify which car brand to be search
        search_car.front() = std::toupper( search_car.front() );
        for(int x=0; x<cnt; x++) //Loop to last account, by using cnt we can stop when the array is a null
        {
            if(search_car==car_brand[x])//Detecting which car brand same as user input
            {
                cout<<"\n\tCar Registration Number:"<<car_num[x]<<endl;
                cout<<"\n\tCar Make or Brand:"<<car_brand[x]<<endl;
                cout<<"\n\tCar Model:"<<car_model[x]<<endl;
                cout<<"\n\tCar Colour:"<<car_colour[x]<<endl;
                cout<<"\n\tYear of Manufacturing:"<<car_year[x]<<endl;
                cout<<"\n\tEngine Capacity:"<<car_eng_cap[x]<<"cc"<<endl;
                cout<<"\n\tTransmission:"<<car_tran[x]<<endl;
                cout<<"\n\tCost of Car: RM"<<car_cost[x]<<endl;
            }
            else
                cout<<"No data is founded."<<endl;
            break;
        }
    }
case 2: //Option 2
    {
        cout<<"Enter Car Model:"<<endl;
        cin>>search_car; //Identify which car model to be search
        search_car.front() = std::toupper( search_car.front() );
        for(int y=0 ; y<cnt ; y++)
        {
            if(search_car==car_model[y])//Detecting which car model same as user input
            {
                cout<<"\n\tCar Registration Number:"<<car_num[y]<<endl;
                cout<<"\n\tCar Make or Brand:"<<car_brand[y]<<endl;
                cout<<"\n\tCar Model:"<<car_model[y]<<endl;
                cout<<"\n\tCar Colour:"<<car_colour[y]<<endl;
                cout<<"\n\tYear of Manufacturing:"<<car_year[y]<<endl;
                cout<<"\n\tEngine Capacity:"<<car_eng_cap[y]<<"cc"<<endl;
                cout<<"\n\tTransmission:"<<car_tran[y]<<endl;
                cout<<"\n\tCost of Car: RM"<<car_cost[y]<<endl;
            }
            else
                cout<<"No data is founded."<<endl;
            break;
        }
    }
case 3: //Option 3
    {
        cout<<"Enter Year of Manufacturing:"<<endl;
        cin>>search_car;
        for(int x=0; x<cnt; x++)
        {
            if(search_car==car_year[x])//Detecting which car manufacturing year same as user input
            {
                cout<<"\n\tCar Registration Number:"<<car_num[x]<<endl;
                cout<<"\n\tCar Make or Brand:"<<car_brand[x]<<endl;
                cout<<"\n\tCar Model:"<<car_model[x]<<endl;
                cout<<"\n\tCar Colour:"<<car_colour[x]<<endl;
                cout<<"\n\tYear of Manufacturing:"<<car_year[x]<<endl;
                cout<<"\n\tEngine Capacity:"<<car_eng_cap[x]<<"cc"<<endl;
                cout<<"\n\tTransmission:"<<car_tran[x]<<endl;
                cout<<"\n\tCost of Car: RM"<<car_cost[x]<<endl;
            }
            else
                cout<<"No data is founded."<<endl;
            break;
        }
    }
case 4: //Option 4
   {
       cout<<"Enter Car Price:"<<endl;
       cin>>search_car;
       for(int x=0 ; x<cnt; x++)
       {
           if(search_car==car_cost[x])//Detecting which car price same as user input
           {
               cout<<"\n\tCar Registration Number:"<<car_num[x]<<endl;
               cout<<"\n\tCar Make or Brand:"<<car_brand[x]<<endl;
               cout<<"\n\tCar Model:"<<car_model[x]<<endl;
               cout<<"\n\tCar Colour:"<<car_colour[x]<<endl;
               cout<<"\n\tYear of Manufacturing:"<<car_year[x]<<endl;
               cout<<"\n\tEngine Capacity:"<<car_eng_cap[x]<<"cc"<<endl;
               cout<<"\n\tTransmission:"<<car_tran[x]<<endl;
               cout<<"\n\tCost of Car: RM"<<car_cost[x]<<endl;
            }
           else
                cout<<"No data is founded."<<endl;
           break;
       }
   }
case 5: //Option 5
    {
        cout<<"Operation Canceled."<<endl;
        break;
    }

好像不管我在option里输入什么数字，输出都会让我输入汽车品牌，在我输入和输入后，它只会弹出我们的第二个选项让我输入汽车型号.. ..似乎开关盒无法正常工作，我该如何解决？

[更新]

这是我想问的另一个问题：

我有这样的代码：

案例1：//选项1

{

cout

cin>>car_brand[x];

}

休息;

我要怎么做才能改变输入的汽车品牌第一个字符是大写的？例如，我输入 toyota，输出将变为 Toyota。

Answer 1

您的breaks 完全放错了地方。

将它们移出for 循环！

Answer 2

您已将 break 语句放在您的 for 循环中，这将使您从循环中中断，然后进入下一个 switch 案例。如果你想从 switch case 中中断，break 语句应该是 switch case 中右大括号之前的最后一行。

case 1:
{
    for(...)
    {
        ...
    }
    break;
}

Answer 3

您的案例结束时没有break。 break 语句位于循环内。

Answer 4

正如已经指出的那样，您的案例是错误的。例如在这种情况下

case 1: //Option 1
    {
        cout<<"Enter Car Brand:"<<endl;
        cin>>search_car; //Identify which car brand to be search
        search_car.front() = std::toupper( search_car.front() );
        for(int x=0; x<cnt; x++) //Loop to last account, by using cnt we can stop when the array is a null
        {
            if(search_car==car_brand[x])//Detecting which car brand same as user input
            {
                cout<<"\n\tCar Registration Number:"<<car_num[x]<<endl;
                cout<<"\n\tCar Make or Brand:"<<car_brand[x]<<endl;
                cout<<"\n\tCar Model:"<<car_model[x]<<endl;
                cout<<"\n\tCar Colour:"<<car_colour[x]<<endl;
                cout<<"\n\tYear of Manufacturing:"<<car_year[x]<<endl;
                cout<<"\n\tEngine Capacity:"<<car_eng_cap[x]<<"cc"<<endl;
                cout<<"\n\tTransmission:"<<car_tran[x]<<endl;
                cout<<"\n\tCost of Car: RM"<<car_cost[x]<<endl;
            }
            else
                cout<<"No data is founded."<<endl;
            break;
        }
    }

您退出循环取决于是否找到汽车。此案例标签的控制也传递给下一个案例标签。

这种情况应该是这样的（我假设只能存在一辆具有给定品牌的汽车，否则您应该在 ;loop 中输出所有信息）

case 1: //Option 1
    {
        cout<<"Enter Car Brand:"<<endl;
        cin>>search_car; //Identify which car brand to be search
        search_car.front() = std::toupper( search_car.front() );

        int x = 0; 
        while ( x < cnt && search_car != car_brand[x] ) x++; //Loop to last account, by using cnt we can stop when the array is a null

        if ( x != cnt )//Detecting which car brand same as user input
        {
            cout<<"\n\tCar Registration Number:"<<car_num[x]<<endl;
            cout<<"\n\tCar Make or Brand:"<<car_brand[x]<<endl;
            cout<<"\n\tCar Model:"<<car_model[x]<<endl;
            cout<<"\n\tCar Colour:"<<car_colour[x]<<endl;
            cout<<"\n\tYear of Manufacturing:"<<car_year[x]<<endl;
            cout<<"\n\tEngine Capacity:"<<car_eng_cap[x]<<"cc"<<endl;
            cout<<"\n\tTransmission:"<<car_tran[x]<<endl;
            cout<<"\n\tCost of Car: RM"<<car_cost[x]<<endl;
        }
        else
        }
            cout<<"No data is founded."<<endl;
        }

        break;
    }

尝试以类似的方式重写所有其他情况。