使用C scanf_s的字符串输入

String input using C scanf_s

我一直在寻找自己的答案，但找不到。
我想插入一部分程序，该程序读取" Hello"之类的字符串并存储并在需要时显示它，以便printf("%s", blah);生成Hello。

这是给我麻烦的代码部分

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char name[64];
scanf_s("%s", name);
printf("Your name is %s", name);

我知道printf不是问题；在提示后输入内容后，程序崩溃。请帮忙吗？

根据ISO / IEC 9899：2011标准的附件K.3.5.3.2中的fscanf_s()规范：

The fscanf_s function is equivalent to fscanf except that the c, s, and [ conversion
specifiers apply to a pair of arguments (unless assignment suppression is indicated by a
*). The first of these arguments is the same as for fscanf. That argument is
immediately followed in the argument list by the second argument, which has type
rsize_t and gives the number of elements in the array pointed to by the first argument
of the pair. If the first argument points to a scalar object, it is considered to be an array of
one element.

和：

The scanf_s function is equivalent to fscanf_s with the argument stdin
interposed before the arguments to scanf_s.

MSDN说类似的话(scanf_s()和fscanf_s())。

您的代码未提供length参数，因此使用了其他一些数字。它并不能确定它会找到什么价值，因此您会从代码中得到怪异的行为。您需要更多类似的内容，其中的换行符可帮助确保实际看到输出。

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char name[64];
if (scanf_s("%s", name, sizeof(name)) == 1)
printf("Your name is %s\
", name);

我在大学课程中经常使用它，因此在Visual Studio(在VS2013中测试)中应该可以正常工作：

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char name[64]; // the null-terminated string to be read
scanf_s("%63s", name, 64);
// 63 = the max number of symbols EXCLUDING '\\0'
// 64 = the size of the string; you can also use _countof(name) instead of that number
// calling scanf_s() that way will read up to 63 symbols (even if you write more) from the console and it will automatically set name[63] = '\\0'
// if the number of the actually read symbols is < 63 then '\\0' will be stored in the next free position in the string
// Please note that unlike gets(), scanf() stops reading when it reaches ' ' (interval, spacebar key) not just newline terminator (the enter key)
// Also consider calling"fflush(stdin);" before the (eventual) next scanf()

参考：https://msdn.microsoft.com/zh-cn/library/w40768et.aspx

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#include<stdio.h>

int main()
{
char name[64];
printf("Enter your name:");
gets(name);
printf("Your name is %s\
", name);
return 0;
}

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#include<stdio.h>

int main()
{
char name[64];

printf("Enter your name:");
scanf("%s", name);
printf("Your name is %s\
", name);

return 0;
}