blocks|key|1369058|text|我会使用值初始化，因为它看起来很干净，而且不容易出错，就像你提到的那样。我看不出这样做有什么坏处。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1369059|不过，在使用结构之后，您可以依靠memset将其清零。|offset|length|style|CODE|1369060|entityMap^0|0|G|6|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@$D|L|E|M|F|G]]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

I would use value initialization because it looks clean and less error prone as you mentioned. I don't see any drawback in doing it.

You might rely on <code>memset</code> to zero out the struct after it has been used though.

blocks|key|1369102|text|这并不常见，但我猜第二种方法也有将浮点数初始化为零的好处。而做memset肯定不会|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1369103|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

not that it's common, but I guess the second way also has the benefit of initializing floats to zero. While doing a memset would certainly not

blocks|key|1369161|text|值初始化，因为它可以在编译时完成。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1369162|同样，它正确地初始化所有POD类型。|1369163|memset()是在运行时完成的。|1369164|如果结构不是POD，那么使用memset()也是可疑的。|1369165|未正确初始化(为零)非整型类型。|1369166|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|N|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|O|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|P|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|K|$]]

The value initialization because it can be done at compile time. 
Also it correctly 0 initializes all POD types.

The memset() is done at runtime. 
Also using memset() is suspect if the struct is not POD. 
Does not correctly initialize (to zero) non int types.

blocks|key|1154149|text|根据结构成员的不同，这两种变体不一定是等价的。memset会将结构设置为全位零，而值初始化会将所有成员初始化为值零。C标准保证它们只对整型相同，而不是浮点值或指针。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1154150|此外，一些API要求将结构真正设置为全位零。例如，Berkeley套接字API以多态方式使用结构，因此必须真正将整个结构设置为零，而不仅仅是明显的值。API文档应该说明结构是否真的需要全位零，但这可能是有缺陷的。|1154151|但如果这些都不适用，或者类似的情况都不适用，那就由你来决定。在定义结构时，我更倾向于值初始化，因为这样可以更清楚地传达意图。当然，如果需要将现有结构置零，memset是唯一的选择(除了手动将每个成员初始化为零，但通常不会这样做，特别是对于大型结构)。|1154152|entityMap^0|N|6|0|0|25|6|0^^$0|@$1|2|3|4|5|6|7|L|8|@$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|P|8|@$9|Q|A|R|B|C]]|D|@]|E|$]]|$1|J|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|K|$]]

Depending on the structure members, the two variants are not necessarily equivalent. <code>memset</code> will set the structure to all-bits-zero whereas value initialization will initialize all members to the value zero. The C standard guarantees these to be the same only for integral types, not for floating-point values or pointers.

Also, some APIs require that the structure really be set to all-bits-zero. For instance, the Berkeley socket API uses structures polymorphically, and there it is important to really set the whole structure to zero, not just the values that are apparent. The API documentation should say whether the structure really needs to be all-bits-zero, but it might be deficient.

But if neither of these, or a similar case, applies, then it's up to you. I would, when defining the structure, prefer value initialization, as that communicates the intent more clearly. Of course, if you need to zeroize an existing structure, <code>memset</code> is the only choice (well, apart from initializing each member to zero by hand, but that wouldn't normally be done, especially for large structures).

blocks|key|1154200|text|在某些编译器中，STRUCT+theStruct+=+{};会在可执行文件中转换为memset(+&theStruct,+0,+sizeof(+STRUCT+)+);。一些C函数已经链接到运行时设置中，因此编译器可以使用这些库函数，如memset/memcpy。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1154201|entityMap^0|8|M|15|16|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

In some compilers <code>STRUCT theStruct = {};</code> would translate to <code>memset( &amp;theStruct, 0, sizeof( STRUCT ) );</code> in the executable. Some C functions are already linked in to do runtime setup so the compiler have these library functions like memset/memcpy available to use.

blocks|key|1154236|text|如果你的struct包含像这样的东西：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1154237|int+a;
char+b;
int+c;|code-block|syntax|javascript|1154238|则将在"b“和"c”之间插入字节填充。memset()会将它们置零，反之亦然，所以会有3个字节的垃圾(如果你的整数是32位的话)。如果您打算使用struct从文件中读取/写入，这可能很重要。|1154239|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

If your struct contains things like :

<pre><code>int a;
char b;
int c;
</code></pre>

Then bytes of padding will be inserted between "b" and "c". memset() will zero those, the other way will not, so there will be 3 bytes of garbage (if your ints are 32 bits). If you intend to use your struct to read/write from a file, this might be important.

In Win32 API programming it's typical to use C <code>struct</code>s with multiple fields. Usually only a couple of them have meaningful values and all others have to be zeroed out. This can be achieved in either of the two ways:

<pre><code>STRUCT theStruct;
memset( &amp;theStruct, 0, sizeof( STRUCT ) );
</code></pre>

or

<pre><code>STRUCT theStruct = {};
</code></pre>

The second variant looks cleaner - it's a one-liner, it doesn't have any parameters that could be mistyped and lead to an error being planted.

Does it have any drawbacks compared to the first variant? Which variant to use and why?

memset() or value initialization to zero out a struct?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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在Win32应用程序接口编程中，通常使用带有多个字段的Cstruct。通常只有几个参数具有有意义的值，而其他所有参数都必须清零。这可以通过以下两种方式中的任何一种实现：STRUCT theStruct;memset( &theStruct, 0, sizeof( STRUCT ) );或STRUCT theStruct...

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