c++ - strcmp 从 'char' 到 'const char*' 的转换

Question

我遇到了 strcmp 的问题。

这是我的代码。

while (strcmp("m",wood) !=0 || strcmp("j",wood) !=0 || strcmp("o",wood) !=0){
    cout << "(m for mahogany, o for oak, or p for pine): ";
cin >> wood;
}

这是我的错误：

dining.cpp: In member function ‘void DiningSet::woodType()’:
dining.cpp:76:24: error: invalid conversion from ‘char’ to ‘const char*’ [-fpermissive]
/usr/include/string.h:143:12: error:   initialising argument 2 of ‘int strcmp(const char*, const char*)’ [-fpermissive]
dining.cpp:76:48: error: invalid conversion from ‘char’ to ‘const char*’ [-fpermissive]
/usr/include/string.h:143:12: error:   initialising argument 2 of ‘int strcmp(const char*, const char*)’ [-fpermissive]
dining.cpp:76:72: error: invalid conversion from ‘char’ to ‘const char*’ [-fpermissive]
/usr/include/string.h:143:12: error:   initialising argument 2 of ‘int strcmp(const char*, const char*)’ [-fpermissive]

Answer 1

woodis of type char: 它必须是一个字符串，即 ,char*用于strcmp().

改成：

while ('m' != wood && 'j' != wood && 'o' != wood)

Answer 2

该错误显示第二个参数有问题。它应该是一个const char *

的签名strcmp是：

int strcmp ( const char * str1, const char * str2 );