blocks|key|1568537|text|你不需要在safe和unsafe前面加星号。它们已经是指针了。此外，您必须使用单引号而不是双引号。单引号用于字符，双引号用于字符串。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1568538|entityMap^0|5|4|A|6|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|$]]

You don't need asterisks in front of <code>safe</code> and <code>unsafe</code>. They're already pointers.
Also, you must use single quotes instead of double quotes. Single quotes are for chars, double quotes are for stings.

blocks|key|552504|text|在您的代码中，safe是指向字符的指针(而不是指向数组的指针)。所以当你说*safe的时候，那是一个普通的char。尝试(*safe)[offset]+safe[offset].而不是(*safe)[offset]*safe[offset]也是如此，unsafe也是如此。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|BOLD|entityRanges|data|552505|第二个问题是比较字符的方式。"\0“是字符串文字。在您的代码中，您需要一个字符文字。简而言之，for应该是：|552506|for+(;+safe[offset]+!=+'\0'+;+offset%2B%2B)|code-block|syntax|javascript|552507|但是，由于\0是0，您可以重写它并使其更简单|552508|for+(offset=0;+safe[offset];+offset%2B%2B)|552509|entityMap^0|7|4|11|5|1H|4|1O|F|24|C|2K|S|3H|6|1O|F|24|C|2K|18|0|0|1I|1B|3|0|0|0|M|5|2|8|1|0|0^^$0|@$1|2|3|4|5|6|7|T|8|@$9|U|A|V|B|C]|$9|W|A|X|B|C]|$9|Y|A|Z|B|C]|$9|10|A|11|B|C]|$9|12|A|13|B|C]|$9|14|A|15|B|C]|$9|16|A|17|B|C]|$9|18|A|19|B|D]|$9|1A|A|1B|B|D]|$9|1C|A|1D|B|D]]|E|@]|F|$]]|$1|G|3|H|5|6|7|1E|8|@$9|1F|A|1G|B|D]|$9|1H|A|1I|B|C]]|E|@]|F|$]]|$1|I|3|J|5|K|7|1J|8|@]|E|@]|F|$L|M]]|$1|N|3|O|5|6|7|1K|8|@$9|1L|A|1M|B|D]|$9|1N|A|1O|B|C]|$9|1P|A|1Q|B|C]]|E|@]|F|$]]|$1|P|3|Q|5|K|7|1R|8|@]|E|@]|F|$L|M]]|$1|R|3|-4|5|6|7|1S|8|@]|E|@]|F|$]]]|S|$]]

In your code <code>safe</code> is a pointer to a char (not a pointer to an array). So when you say <code>*safe</code> that's a plain <code>char</code>. Instead of <code>(*safe)[offset]</code> try <code>safe[offset]</code>. Same goes for <code>*safe[offset]</code>, same goes for <code>unsafe</code>.

A second problem is the way you are comparing characters. "\0" is a string literal. In your code you want a character literal. In short, the <code>for</code> should be:

<pre><code>for (; safe[offset] != '\0' ; offset++)
</code></pre>

But you could rewrite it and make it simpler, since <code>\0</code> is <code>0</code>:

<pre><code>for (offset=0; safe[offset]; offset++)
</code></pre>

blocks|key|4678156|text|字符常量需要单引号而不是双引号：'\0',+'\n',+'\r',+and+'~'|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4678157|此外，分配给safe可能是不允许的，因为它被标记为const+(在修复了其他答案中已经提到的间接问题之后)。|4678158|entityMap^0|G|P|0|6|4|P|5|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|R|8|@]|D|@]|E|$]]]|I|$]]

The character constants need single quotes instead of double quotes: <code>'\0', '\n', '\r', and '~'</code>

Also, the assignment to the <code>safe</code> probably will not be allowed since it is marked as <code>const</code> (after fixing the indirection issues already mentioned in other answers).

blocks|key|551925|text|指针unsafe和safe指向字符数组的第一项。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|551926|safe[4]将是数组中的第五项(从零开始计数)，即第五个字符|551927|所以代码应该是|551928|void+makesafestr+(+const+char+*unsafe,++char+*safe+)++/*+Do+not+need+const+for+safe,+as+you+are
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++constructing+it+*/
{++
++int+offset=0;++
++for+(;+unsafe[offset]+!=+0+;+offset%2B%2B)+/*+Do+not+need+the+"+-+see+below.+Also+would+have
++++++++++++++++++++++++++++++++++++++++++++thought+you+need+to+scan+unsafe+*/
++{++
++++++switch+(unsafe[offset])+{++
++++++++case+'\n':++/*+Single+quotes+required+as+we+are+dealing+with+characters+and+not+strings+*/
++++++++case+'\r':++
++++++++++safe[offset]+=+'~';++
++++++++++break;++
+++++++default:++
++++++++++safe[offset]+=+unsafe[offset];++
+++++}++
+++++offset%2B%2B;+
+++}
+++safe[offset]+=+0;+/*+In+C+and+C%2B%2B+strings+end+with+the+null+character+*/++
}|code-block|syntax|javascript|551929|注意，C和C%2B%2B中的字符串("a+string")是一个字符数组。|551930|entityMap^0|2|6|9|4|0|0|7|0|0|0|E|A|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|X|8|@$9|Y|A|Z|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|10|8|@]|D|@]|E|$]]|$1|J|3|K|5|L|7|11|8|@]|D|@]|E|$M|N]]|$1|O|3|P|5|6|7|12|8|@$9|13|A|14|B|C]]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|15|8|@]|D|@]|E|$]]]|R|$]]

The pointer <code>unsafe</code> and <code>safe</code> point to the first item of the character array.

<code>safe[4]</code> will be the fifth item (counting from zero) in the array i.e. the fifth character

So the code should be

<pre><code>void makesafestr ( const char *unsafe, char *safe ) /* Do not need const for safe, as you are
 constructing it */
{ 
 int offset=0; 
 for (; unsafe[offset] != 0 ; offset++) /* Do not need the " - see below. Also would have
 thought you need to scan unsafe */
 { 
 switch (unsafe[offset]) { 
 case '\n': /* Single quotes required as we are dealing with characters and not strings */
 case '\r': 
 safe[offset] = '~'; 
 break; 
 default: 
 safe[offset] = unsafe[offset]; 
 } 
 offset++; 
 }
 safe[offset] = 0; /* In C and C++ strings end with the null character */ 
}
</code></pre>

Note, a string (<code>"a string"</code>) in C and C++ is an array of characters.

This should be simple, but pointers to char arrays still leave me scratching my head sometimes. gcc complains that "subscripted value is neither array nor pointer" in lines 4 and 5, and "invalid type argument of 'unary *'" on lines 8 and 11. Can someone explain what is going wrong here? I changed lines 4 and 5 to dereference the pointer first using brackets, but still can't get what I want.

This should be a pretty simple function:

<pre><code>1 void makesafestr ( const char *unsafe, const char *safe )
2 {
3 int offset=0;
4 for (; (*safe)[offset] != "\0" ; offset++) {
5 switch ((*unsafe)[offset]) {
6 case "\n":
7 case "\r":
8 *safe[offset] = "~";
9 break;
10 default:
11 *safe[offset] = *unsafe[offset];
12 }
13 offset++;
14 }
}
</code></pre>

C pointer confusion - pointer to char array

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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这应该很简单，但是指向char数组的指针有时仍然让我摸不着头脑。gcc抱怨第四行和第五行“下标的值既不是数组也不是指针”，以及第八行和第十一行“一元*的无效类型参数”，有谁能解释一下这里出了什么问题吗？我更改了第4行和第5行，首先使用括号取消了对指针的引用，但仍然无法获得我想要的结果。这应该是一个非常简单的函数：1  ...

问C指针混淆-指向字符数组的指针
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