C++无法使用枚举和切换在一起

Question

从我所看到的,我应该能够在枚举上运行一个开关,但是我正在吐出错误:

enum EMETH {TRAP=1, SIMP=2, MIDP=3, SINF=4};



switch(METH)
{
    case "TRAP":
        Meth=&Integrators::Trap;
        break;
    case "SIMP":
        Meth=&Integrators::Simp;
        break;
    case "MIDP":
        Meth=&Integrators::Midp;
        break;
    case "SINF":
        Meth=&Integrators::SInf;
        break;
}

错误是

 error: invalid conversion from ‘const char*’ to ‘int’ [-fpermissive]
       case "TRAP":
 error: ‘(int)((long int)"TRAP")’ is not a constant expression

对于每个案例.

Answer 1

通过在枚举成员的名称周围加上引号,你已经使它们成为字符串常量.因此,您正在进行无效转换的错误.switch语句在序数上运行,这就是枚举成员.所以删除"".

enum EMETH {TRAP=1, SIMP=2, MIDP=3, SINF=4};

switch(METH)
{
    case TRAP:
        Meth=&Integrators::Trap;
        break;
    case SIMP:
        Meth=&Integrators::Simp;
        break;
    case MIDP:
        Meth=&Integrators::Midp;
        break;
    case SINF:
        Meth=&Integrators::SInf;
        break;
}