blocks|key|413725|text|在C%2B%2B11之前，您不能使用type[]初始化数组。但是最新的c%2B%2B11提供了(统一的)初始化，所以你可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|413726|string*+pStr+=+new+string[3]+{+"hi",+"there"};|code-block|syntax|javascript|413727|请参阅http://www2.research.att.com/~bs/C%2B%2B0xFAQ.html#uniform-init|offset|length|413728|entityMap|0|LINK|mutability|MUTABLE|url|http://www2.research.att.com/~bs/C%2B%2B0xFAQ.html#uniform-init^0|0|0|3|1N|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

Prior to C++11, you cannot initialise an array using type[]. However the latest c++11 provides(unifies) the initialisation, so you can do it in this way:

<pre><code>string* pStr = new string[3] { "hi", "there"};
</code></pre>

See <a href="http://www2.research.att.com/~bs/C++0xFAQ.html#uniform-init">http://www2.research.att.com/~bs/C++0xFAQ.html#uniform-init</a>

blocks|key|628959|text|有了对C%2B%2B11初始化器列表的支持，这非常容易：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|628960|#include+<iostream>
#include+<vector>
#include+<string>
using+namespace+std;

using+Strings+=+vector<string>;

void+foo(+Strings+const&+strings+)
{
++++for(+string+const&+s+:+strings+)+{+cout+<<+s+<<+endl;+}
}

auto+main()+->+int
{
++++foo(+Strings{+"hi",+"there"+}+);+
}|code-block|syntax|javascript|628961|如果缺少这些(例如，对于Visual+C%2B%2B+10.0)，您可以这样做：|628962|#include+<iostream>
#include+<vector>
#include+<string>
using+namespace+std;

typedef+vector<string>+Strings;

void+foo(+Strings+const&+strings+)
{
++++for(+auto+it+=+begin(+strings+);++it+!=+end(+strings+);++%2B%2Bit+)
++++{
++++++++cout+<<+*it+<<+endl;
++++}
}

template<+class+Elem+>
vector<Elem>&+r(+vector<Elem>&&+o+)+{+return+o;+}

template<+class+Elem,+class+Arg+>
vector<Elem>&+operator<<(+vector<Elem>&+v,+Arg+const&+a+)
{
++++v.push_back(+a+);
++++return+v;
}

int+main()
{
++++foo(+r(+Strings()+)+<<+"hi"+<<+"there"+);+
}|628963|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|$]]

With support for C++11 initializer lists it is very easy:

<pre><code>#include &lt;iostream&gt;
#include &lt;vector&gt;
#include &lt;string&gt;
using namespace std;

using Strings = vector&lt;string&gt;;

void foo( Strings const&amp; strings )
{
 for( string const&amp; s : strings ) { cout &lt;&lt; s &lt;&lt; endl; }
}

auto main() -&gt; int
{
 foo( Strings{ "hi", "there" } ); 
}
</code></pre>

Lacking that (e.g. for Visual C++ 10.0) you can do things like this:

<pre><code>#include &lt;iostream&gt;
#include &lt;vector&gt;
#include &lt;string&gt;
using namespace std;

typedef vector&lt;string&gt; Strings;

void foo( Strings const&amp; strings )
{
 for( auto it = begin( strings ); it != end( strings ); ++it )
 {
 cout &lt;&lt; *it &lt;&lt; endl;
 }
}

template&lt; class Elem &gt;
vector&lt;Elem&gt;&amp; r( vector&lt;Elem&gt;&amp;&amp; o ) { return o; }

template&lt; class Elem, class Arg &gt;
vector&lt;Elem&gt;&amp; operator&lt;&lt;( vector&lt;Elem&gt;&amp; v, Arg const&amp; a )
{
 v.push_back( a );
 return v;
}

int main()
{
 foo( r( Strings() ) &lt;&lt; "hi" &lt;&lt; "there" ); 
}
</code></pre>

blocks|key|413817|text|在C%2B%2B11中您可以这样做。事先要注意的是:不要对数组执行new操作，没有必要这样做。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|413818|首先，string[]+strArray是一个语法错误，应该是string*+strArray或string+strArray[]。我假设只是为了这个例子，你不需要传递任何size参数。|413819|#include+<string>

void+foo(std::string*+strArray,+unsigned+size){
++//+do+stuff...
}

template<class+T>
using+alias+=+T;

int+main(){
++foo(alias<std::string[]>{"hi",+"there"},+2);
}|code-block|syntax|javascript|413820|请注意，如果您不需要将数组大小作为额外的参数传递，效果会更好，谢天谢地有一种方法:模板！|413821|template<unsigned+N>
void+foo(int+const+(&arr)[N]){
++//+...
}|413822|请注意，这将只与堆栈数组匹配，如int+x[5]+=+...。或者通过使用上面的alias创建的临时文件。|413823|int+main(){
++foo(alias<int[]>{1,+2,+3});
}|413824|entityMap^0|T|3|0|3|H|V|G|1C|H|0|0|0|0|G|E|14|5|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Z|8|@$9|10|A|11|B|C]|$9|12|A|13|B|C]|$9|14|A|15|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|16|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|17|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|18|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|19|8|@$9|1A|A|1B|B|C]|$9|1C|A|1D|B|C]]|D|@]|E|$]]|$1|S|3|T|5|J|7|1E|8|@]|D|@]|E|$K|L]]|$1|U|3|-4|5|6|7|1F|8|@]|D|@]|E|$]]]|V|$]]

In C++11 you can. A note beforehand: Don't <code>new</code> the array, there's no need for that.

First, <code>string[] strArray</code> is a syntax error, that should either be <code>string* strArray</code> or <code>string strArray[]</code>. And I assume that it's just for the sake of the example that you don't pass any size parameter.

<pre><code>#include &lt;string&gt;

void foo(std::string* strArray, unsigned size){
 // do stuff...
}

template&lt;class T&gt;
using alias = T;

int main(){
 foo(alias&lt;std::string[]&gt;{"hi", "there"}, 2);
}
</code></pre>

Note that it would be better if you didn't need to pass the array size as an extra parameter, and thankfully there is a way: Templates!

<pre><code>template&lt;unsigned N&gt;
void foo(int const (&amp;arr)[N]){
 // ...
}
</code></pre>

Note that this will only match stack arrays, like <code>int x[5] = ...</code>. Or temporary ones, created by the use of <code>alias</code> above.

<pre><code>int main(){
 foo(alias&lt;int[]&gt;{1, 2, 3});
}
</code></pre>

blocks|key|629060|text|在C%2B%2B11及更高版本中，您还可以使用初始化器列表来初始化std::vector。例如：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|629061|using+namespace+std;+//+for+example+only

for+(auto+s+:+vector<string>{"one","two","three"}+)+
++++cout+<<+s+<<+endl;|code-block|syntax|javascript|629062|因此，您的示例将变为：|629063|void+foo(vector<string>+strArray){
++//+some+code
}

vector<string>+s+{"hi",+"there"};+//+Works
foo(s);+//+Works

foo(vector<string>+{"hi",+"there"});+//+also+works|629064|entityMap^0|T|B|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|P|$]]

In C++11 and above, you can also initialize <code>std::vector</code> with an initializer list. For example:

<pre><code>using namespace std; // for example only

for (auto s : vector&lt;string&gt;{"one","two","three"} ) 
 cout &lt;&lt; s &lt;&lt; endl;
</code></pre>

So, your example would become:

<pre><code>void foo(vector&lt;string&gt; strArray){
 // some code
}

vector&lt;string&gt; s {"hi", "there"}; // Works
foo(s); // Works

foo(vector&lt;string&gt; {"hi", "there"}); // also works
</code></pre>

I know I can do this in C++:

<pre><code>string s[] = {"hi", "there"};
</code></pre>

But is there anyway to delcare an array this way without delcaring <code>string s[]</code>?

e.g.

<pre><code>void foo(string[] strArray){
 // some code
}

string s[] = {"hi", "there"}; // Works
foo(s); // Works

foo(new string[]{"hi", "there"}); // Doesn't work
</code></pre>

c++ string array initialization

我知道我可以在C++中做到这一点：string s[] = {"hi", "there"};但是，有没有办法以这种方式去关心一个数组而不去关心string s[]呢？例如：void foo(string[] strArray){  // some code}string s[] = {"hi", "there"}; /...

问c++ string数组初始化
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