您如何在C中定义常量？ [英] How do you define a constant in C?

问题描述

我正在尝试构建一个开关，但显示表达式必须具有整数或枚举类型。我猜想winapi中的开关不会接受LPSTR类型的变量？

I'm trying to build a switch and I get an "expression must have integral or enum type". I'm guessing the switch in winapi doesn't take variables with LPSTR type?

char testbuf[ 51 ]; // allocate space for 50 characters + termination
LPSTR test = testbuf;
scanf("%50s", test); // read at most 50 characters
printf("%s", test);
switch ( test ) {
    case "etc" :
        {

        }
    break;

推荐答案

我通常使用一种字典模式：

I usually use a kind of dictionary pattern:

enum {
    keyETC,
    keyOther,
    keyUnknown
};
struct SDictionary{
    int key;
    char *name;
} dict[] = {
    { keyETC, "etc" },
    { keyOther, "bla" },
    { 0 }
};

// lookup
struct SDictionary *pCandidate = dict;
int key = keyUnknown;

while (pCandidate->name)
{
    if (0 == strcmp(test, pCandidate->name)
    {
         key = pCandidate->key;
         break;
    }
}

switch (key)
{
    case keyETC:
    // ....
}

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