blocks|key|1432735|text|取决于你所说的“空”是什么意思：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1432736|members[0]+=+'\0';|code-block|syntax|javascript|1432737|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Depends on what you mean by 'empty':

<pre><code>members[0] = '\0';
</code></pre>

blocks|key|1218163|text|如果您正在处理字符串，请不要费心将char数组清零。下面是使用char字符串的一种简单方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1218164|复制(分配新字符串)：|1218165|strcpy(members,+"hello");|code-block|syntax|javascript|1218166|连接(添加字符串)：|1218167|strcat(members,+"+world");|1218168|空字符串：|1218169|members[0]+=+0;|1218170|就这么简单。|1218171|entityMap^0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|Z|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|10|8|@]|9|@]|A|$G|H]]|$1|Q|3|R|5|6|7|11|8|@]|9|@]|A|$]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

Don't bother trying to zero-out your char array if you are dealing with strings. Below is a simple way to work with the char strings.

Copy (assign new string):

<pre><code>strcpy(members, "hello");
</code></pre>

Concatenate (add the string):

<pre><code>strcat(members, " world");
</code></pre>

Empty string:

<pre><code>members[0] = 0;
</code></pre>

Simple like that.

blocks|key|1432662|text|char+members255+=+{0}；|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1432663|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|$]]

blocks|key|1218187|text|使用bzero(array+name,+no.of+bytes+to+be+cleared);|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1218188|entityMap^0|2|19|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

Use <code>bzero(array name, no.of bytes to be cleared);</code>

blocks|key|1432854|text|您不能这样清空数组，它始终包含相同数量的数据。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1432855|在更大的上下文中，数组中的数据可能表示一个空的项目列表，但这必须在数组之外定义。最常见的方法是对有效项进行计数(参见pmg的答案)，或者让字符串以零字符结束(Felix的答案)。还有更复杂的方法，例如，环形缓冲区使用两个索引来表示添加和删除数据的位置。|1432856|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

You cannot empty an array as such, it always contains the same amount of data.

In a bigger context the data in the array may represent an empty list of items, but that has to be defined in addition to the array. The most common ways to do this is to keep a count of valid items (see the answer by pmg) or for strings to terminate them with a zero character (the answer by Felix). There are also more complicated ways, for example a ring buffer uses two indices for the positions where data is added and removed.

blocks|key|1432901|text|members[0]+=+0;|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1432902|已经足够了，考虑到你的需求。|unstyled|1432903|但是请注意，这并不是“清空”缓冲区。内存仍然被分配，有效的字符值可能仍然存在，以此类推。|1432904|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|L|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|F|7|N|8|@]|9|@]|A|$]]]|J|$]]

<pre><code>members[0] = 0;
</code></pre>

is enough, given your requirements.

Notice however this is not "emptying" the buffer. The memory is still allocated, valid character values may still exist in it, and so forth..

blocks|key|1432654|text|如果是我的话|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1432655|members_in_use+=+0;|code-block|syntax|javascript|1432656|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I'd go with

<pre><code>members_in_use = 0;
</code></pre>

blocks|key|1432787|text|通过“清空数组”，如果你的意思是重置为0，那么你可以使用bzero。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1432788|#include+<strings.h>++
void+bzero(void+*s,+size_t+n);++|code-block|syntax|javascript|1432789|如果你想用其他默认字符填充数组，那么你可以使用memset函数。|1432790|#include+<string.h>++
void+*memset(void+*s,+int+c,+size_t+n);++|1432791|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

By "empty an array" if you mean reset to 0, then you can use bzero. 

<pre><code>#include &lt;strings.h&gt; 
void bzero(void *s, size_t n); 
</code></pre>

If you want to fill the array with some other default character then you may use memset function. 

<pre><code>#include &lt;string.h&gt; 
void *memset(void *s, int c, size_t n); 
</code></pre>

blocks|key|1432946|text|在这种情况下，只有members[0]+=+0可以工作。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1432947|entityMap^0|9|E|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

In this case just <code>members[0] = 0</code> works.

blocks|key|1433033|text|您可以使用以下指令：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1433034|strcpy_s(members,+"");|code-block|syntax|javascript|1433035|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can use the following instruction:

<pre><code>strcpy_s(members, "");
</code></pre>

Have an array of chars like char members[255]. How can I empty it completely without using a loop?

<pre><code>char members[255];
</code></pre>

By "empty" I mean that if it had some values stored in it then it should not. For example if I do strcat then old value should not remain

<pre><code>members = "old value";

//empty it efficiently
strcat(members,"new"); // should return only new and not "old value new"
</code></pre>

How to empty a char array?

有一个像char members255这样的字符数组。如何在不使用循环的情况下完全清空它？char members[255];我所说的“空”的意思是，如果它有一些值存储在里面，那么它就不应该存储。例如，如果我使用strcat，则旧值不应保留members = "old value";//empty it efficientlystrcat(members,"new"); // should ret

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