blocks|key|155342|text|看起来你必须显式地传递一个字符类型给它才能起作用。这对我很有效。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|155343|let+char+=+Character("a")
let+string+=+String(count:+5,+repeatedValue:+char)|code-block|syntax|javascript|155344|尽管如此，也可能会有一些bug混杂在这一切之中。我相信你做这件事的方式应该是有效的。而且我似乎根本不能在这个初始化器上获得代码完成。|155345|编辑:我将使用bug。下面的代码编译得很好。|155346|let+array+=+Array(count:+5,+repeatedValue:+"a")|155347|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|S|8|@]|9|@]|A|$E|F]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

It seems that you have to explicitly pass in a Character type to it to function. This works for me.

<pre><code>let char = Character("a")
let string = String(count: 5, repeatedValue: char)
</code></pre>

Although, there may be bug mixed in with all this as well. I believe the way you were doing this should have worked on its own. And I can't seem to get code completion on this initializer at all.

Edit: I'm going with bug. The following compiles just fine.

<pre><code>let array = Array(count: 5, repeatedValue: "a")
</code></pre>

blocks|key|2737471|text|这个很好用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2737472|var+str9+=+String(count:+5,repeatedValue:+Character("c"))|code-block|syntax|javascript|2737473|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|$]]

This works just fine : 

<pre><code>var str9 = String(count: 5,repeatedValue: Character("c"))
</code></pre>

blocks|key|2950233|text|我知道这是一个古老的问题，而且已经有了答案。然而，我想我知道为什么+String(count:+5,+repeatedValue:+"a")不能工作了。|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|CODE|entityRanges|data|2950234|问题是String有两个看起来相似的initialisers|2950235|init(count:+Int,+repeatedValue:+Character)
init(count:+Int,+repeatedValue:+UnicodeScalar)|code-block|syntax|javascript|2950236|因此，在这种情况下，编译器无法判断文字是Character还是UnicodeScalar，因此，如果不传递显式的Character，则编译时会出错。要确认可以将"a"解释为UnicodeScalar，可以检查以下代码行是否已编译：|2950237|let+a:+UnicodeScalar+=+"a"|2950238|entityMap|0|LINK|mutability|MUTABLE|url|http://swiftdoc.org/v2.2/type/String/#init-count_-int-repeatedvalue_-character^0|U|3|Y|10|0|3|6|I|C|0|0|0|K|9|V|D|1K|9|28|3|2E|D|0|0^^$0|@$1|2|3|4|5|6|7|Z|8|@$9|10|A|11|B|C]|$9|12|A|13|B|D]]|E|@]|F|$]]|$1|G|3|H|5|6|7|14|8|@$9|15|A|16|B|D]]|E|@$9|17|A|18|1|19]]|F|$]]|$1|I|3|J|5|K|7|1A|8|@]|E|@]|F|$L|M]]|$1|N|3|O|5|6|7|1B|8|@$9|1C|A|1D|B|D]|$9|1E|A|1F|B|D]|$9|1G|A|1H|B|D]|$9|1I|A|1J|B|D]|$9|1K|A|1L|B|D]]|E|@]|F|$]]|$1|P|3|Q|5|K|7|1M|8|@]|E|@]|F|$L|M]]|$1|R|3|-4|5|6|7|1N|8|@]|E|@]|F|$]]]|S|$T|$5|U|V|W|F|$X|Y]]]]

I know this is an old question and already has an answer. However I think I know why <code>String(count: 5, repeatedValue: "a")</code> does not work.

The thing is <code>String</code> has two similar looking <a href="http://swiftdoc.org/v2.2/type/String/#init-count_-int-repeatedvalue_-character" rel="nofollow">initialisers</a>:

<pre><code>init(count: Int, repeatedValue: Character)
init(count: Int, repeatedValue: UnicodeScalar)
</code></pre>

So in this case compiler can't tell whether a literal is a <code>Character</code> or <code>UnicodeScalar</code>, hence compile time error if you don't pass explicit <code>Character</code>. To confirm that <code>"a"</code> can be interpreted as <code>UnicodeScalar</code> you can check that this line compiles:

<pre><code>let a: UnicodeScalar = "a"
</code></pre>

blocks|key|152570|text|为了将来的搜索者的利益:从Swift+3开始，使用init(repeating:count:)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|152571|let+sososo+=+String(repeating:+"so",+count:+3)|code-block|syntax|javascript|152572|entityMap^0|P|M|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

For the benefit of future searchers: as of Swift 3, use <code>init(repeating:count:)</code>.

<pre><code>let sososo = String(repeating: "so", count: 3)
</code></pre>

blocks|key|2737514|text|Swift+3:|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|2737515|var+array+=+Array(repeating:+0,+count:+5)|code-block|syntax|javascript|2737516|输出:+0，0，0，0，0|2737517|entityMap^0|0|8|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|S|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

Swift 3: 

<pre><code>var array = Array(repeating: 0, count: 5)
</code></pre>

Output: [0, 0, 0, 0, 0]

blocks|key|2950253|text|对于swift+3.x中的任何人来说，现在就像这样，这将是一种魅力。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2950254|var+string+=+String(repeating:+"a",+count:+5)|code-block|syntax|javascript|2950255|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|$]]

For anyone in swift 3.x its now something like this this will work like a charm.

<pre><code>var string = String(repeating: "a", count: 5)
</code></pre>

Tested this from the reference: <a href="https://developer.apple.com/documentation/swift" rel="noreferrer">https://developer.apple.com/documentation/swift</a>

<pre><code>var string = String(count: 5, repeatedValue: "a")
// string is "aaaaa"
</code></pre>

I got this error:

<blockquote>
 Playground execution failed: error: :5:14: error: could not find an overload for 'init' that accepts the supplied arguments
 var string = String(count: 5, repeatedValue: "a")
</blockquote>

Does this actually work?

Does Swift init(count:, repeatedValue:) work?

编译器

Swift

从参考资料中测试了这一点var string = String(count: 5, repeatedValue: "a")// string is "aaaaa"我得到了这个错误：游乐场执行失败:错误：:5:14:错误:找不到接受所提供参数的'init‘的重载变量字符串=字符串(计数: 5，repeatedValue：...

问Swift init(count:，repeatedValue:)能工作吗？
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