blocks|key|412556|text|"red",+"orange",+"yellow",+"blue"|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|412557|这些是常量字符串。创建指向常量字符串的非常数指针是错误的，因此出现警告。现在你会收到一个警告，但这应该是一个错误，因为它在c%2B%2B03中已被弃用，并在c%2B%2B11中被禁止。|unstyled|412558|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>"red", "orange", "yellow", "blue"
</code></pre>

these are constant string. Creating a non-const pointer to a constant string is wrong, hence the warning. At the moment you are getting a warning, but it should be an error since it is deprecated in c++03, and forbiden in c++11.

blocks|key|412609|text|您输入的字符串："red“、"organge”等是“文字”，因为它们是在程序代码本身中定义的(它们不是直接从磁盘、用户输入/stdin等读取的)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|412610|这意味着，如果您在任何时候尝试写入colors，您将直接访问原始输入，从而对其进行编辑。这将导致一些不需要的运行时错误。|offset|length|style|CODE|412611|将其声明为const将确保您永远不会尝试写入此指针，并且可以避免此类运行时错误。|412612|const+char+*colors[4]+=+{"red",+"orange",+"yellow",+"blue"};|code-block|syntax|javascript|412613|如果你想在运行时编辑这些值，那么你应该先复制字符串。|412614|entityMap^0|0|H|6|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@$D|U|E|V|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|W|8|@]|9|@]|A|$]]|$1|J|3|K|5|L|7|X|8|@]|9|@]|A|$M|N]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

The strings that you enter: "red", "organge" etc are "literal", because they are defined inside the program code itself (they are not read directly from disk, user input /stdin etc.).

This means that if at any point you try to write to your <code>colors</code> you will be directly accessing your original input and thus editing it. This would cause some undesired run-time errors.

Declaring it as a const will make sure that you will never try to write to this pointer and such a run-time error can be avoided.

<pre><code>const char *colors[4] = {"red", "orange", "yellow", "blue"};
</code></pre>

If you ever feel like editing these values at runtime, then you should copy the strings first.

blocks|key|412649|text|这些答案都是正确的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|412650|请注意，如果您有一个需要以字符数组作为参数的函数，并且您按如下方式传递此参数：|412651|foo+("bar");|code-block|syntax|javascript|412652|将显示相同的警告。在这种情况下，您可以：|412653|1)如下所示，如第一个答案所述：|412654|void+foo+(char[]+str)+{+printf(str);+}

const+char+param[]+=+"bar";
foo+(param);|412655|2)考虑使用C%2B%2B标准字符串，如下所示：|412656|void+foo+(std::string+theParam)+{+std::cout+<<+theParam;+}

foo+("bar");|412657|只要没有真正的性能问题，并且您没有使用C库，或者如果您正在构建一个供他人使用的C%2B%2B库，那么您应该使用C%2B%2B不可变字符串及其特性集。|412658|如果Unicode是必需的，那么正如here所解释的那样，C%2B%2B中的支持是“可怕的”。This+question提供了一些线索(主要是:使用ICU库)。如果你的项目中已经有了Qt，QString和Gettext也可以做到这一点。|offset|length|style|CODE|412659|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/17103925/how-well-is-unicode-supported-in-c11|1|https://stackoverflow.com/questions/55641/unicode-processing-in-c^0|0|0|0|0|0|0|0|0|0|2I|7|I|4|0|17|D|1|0^^$0|@$1|2|3|4|5|6|7|1A|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|1B|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|1C|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|1D|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|1E|8|@]|9|@]|A|$]]|$1|M|3|N|5|F|7|1F|8|@]|9|@]|A|$G|H]]|$1|O|3|P|5|6|7|1G|8|@]|9|@]|A|$]]|$1|Q|3|R|5|F|7|1H|8|@]|9|@]|A|$G|H]]|$1|S|3|T|5|6|7|1I|8|@]|9|@]|A|$]]|$1|U|3|V|5|6|7|1J|8|@$W|1K|X|1L|Y|Z]]|9|@$W|1M|X|1N|1|1O]|$W|1P|X|1Q|1|1R]]|A|$]]|$1|10|3|-4|5|6|7|1S|8|@]|9|@]|A|$]]]|11|$12|$5|13|14|15|A|$16|17]]|18|$5|13|14|15|A|$16|19]]]]

These answers are all correct.

Note that if you have a function requiring an array of characters as an argument and you pass this argument like this:

<pre><code>foo ("bar");
</code></pre>

the same warning will be shown. In this case, you can either :

1) Change it like this, as explained in the first answer:

<pre><code>void foo (char[] str) { printf(str); }

const char param[] = "bar";
foo (param);
</code></pre>

2) Consider using a C++ standard string, like so:

<pre><code>void foo (std::string theParam) { std::cout &lt;&lt; theParam; }

foo ("bar");
</code></pre>

IMHO, as long as no real performance issue is concerned and you are not working with C libraries, or if you are building a C++ library for others to use, you should rather work with C++ immutable strings and their feature set.

If Unicode is a requirement, the support in C++ is "terrible" as explained <a href="https://stackoverflow.com/questions/17103925/how-well-is-unicode-supported-in-c11">here</a>.
<a href="https://stackoverflow.com/questions/55641/unicode-processing-in-c">This question</a> gives you some clues (mainly: use IBM ICU library). If you already have Qt in your project, <code>QString</code> will also do the trick, and so will Gettext.

I have a program which declares an array of strings like this:

<pre><code>char *colors[4] = {"red", "orange", "yellow", "blue"};
</code></pre>

But I get the above compiler warning. It compiles but I'd rather use the non-deprecated way(if there is one). I've tried to find out what it means, but I can't seem to figure it out. I've heard using 'const' before 'char' works, but it would be helpful if someone could explain what the error means. Thanks.

Deprecated conversion from string literal to 'char*'

编译器

我有一个程序，它声明一个字符串数组，如下所示：char *colors[4] = {"red", "orange", "yellow", "blue"};但是我得到了上面的编译器警告。它可以编译，但我更喜欢使用非弃用的方式(如果有)。我试着找出它是什么意思，但我似乎不能理解它。在'char‘起作用之前，我听说过'con...

问不推荐使用从字符串文字到'char*‘的转换
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