为什么在C ++中不是（“ Maya” ==“ Maya”）？ [英] Why isn't ("Maya" == "Maya") true in C++?

问题描述

有人知道为什么由于此代码而得到玛雅不是玛雅人的意思吗？

Any idea why I get "Maya is not Maya" as a result of this code?

if ("Maya" == "Maya") 
   printf("Maya is Maya \n");
else
   printf("Maya is not Maya \n");

推荐答案

因为您实际上是在比较两个指针-使用例如而是以下之一：

Because you are actually comparing two pointers - use e.g. one of the following instead:

if (std::string("Maya") == "Maya") { /* ... */ } 
if (std::strcmp("Maya", "Maya") == 0) { /* ... */ }

这是因为C ++ 03，§2.13.4表示：

This is because C++03, §2.13.4 says:

普通字符串文字的类型为 n const char 的数组

...，在您的情况下，需要进行指针转换。

... and in your case a conversion to pointer applies.

另请参见这个问题有关您为何无法为 == 在这种情况下。

See also this question on why you can't provide an overload for == for this case.

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