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C库函数用法有什么问题?

[英]What's wrong with this C library function usage?

I am trying to compare two char arrays. 我正在尝试比较两个char数组。 The DoSomething() function, however, never get's called. 但是,DoSomething()函数永远不会被调用。 I can't figure out why. 我不知道为什么。

What am I doing wrong? 我究竟做错了什么?

//The value the user types in will be stored here:
char TempStorage[]={0,0,0,0,0,0};

//User types in a sequence here:
GetInput();

//One of the sequences that TempStorage will be compared to.
char Sequence[]={1,2,3,4,0,0};


//If the user typed in "123400" then DoSomething().
if(memcmp(TempStorage, Sequence, sizeof(TempStorage) == 0))
{
    DoSomething();
}

Misplaced paren. 放置错误的括号。

if(memcmp(TempStorage, Sequence, sizeof(TempStorage) == 0))

should be 应该

if(memcmp(TempStorage, Sequence, sizeof(TempStorage)) == 0)

Are those really six inputs that you parsed and placed in an array? 您解析并放置在数组中的那六个输入是真的吗? Or is TempStorage a string of ASCII characters that was input? 还是TempStorage是输入的ASCII字符字符串? If it's the latter, you should be using a string comparison, and you should be using the proper ASCII codes for the character you want to compare. 如果是后者,则应该使用字符串比较,并且应该对要比较的字符使用正确的ASCII码。 (This is 0x30 or '1'' for 1 .) A string comparison stops as soon as one of the strings is a NUL ( '\\0'`), meaning you don't compare meaningless padding if any exists. (这是0x30'1'' for 1” .) A string comparison stops as soon as one of the strings is a NUL ( '\\ 0'`), .) A string comparison stops as soon as one of the strings is a NUL ( ,这意味着您不会比较无意义的填充(如果存在)。

char *input = GetInput();
if (strcmp(input, "1234") == 0) { ... }

your characters will resolve to ASCII values so you should specify it as: 您的字符将解析为ASCII值,因此您应将其指定为:

 char Sequence[]={'1','2','3','4',0,0};

Or compare against an actual string like: 或与实际字符串进行比较,例如:

char Sequence[]="1234";

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