blocks|key|1628931|text|不幸/幸运的是，string类是密封的，所以您不能继承它并重载*运算符。不过，您可以创建扩展方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1628932|public+static+string+Multiply(this+string+source,+int+multiplier)
{
+++StringBuilder+sb+=+new+StringBuilder(multiplier+*+source.Length);
+++for+(int+i+=+0;+i+<+multiplier;+i%2B%2B)
+++{
+++++++sb.Append(source);
+++}

+++return+sb.ToString();
}

string+s+=+"</li></ul>".Multiply(10);|code-block|syntax|javascript|1628933|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|$]]

Unfortunately / fortunately, the string class is sealed so you can't inherit from it and overload the * operator. You can create an extension method though:

<pre><code>public static string Multiply(this string source, int multiplier)
{
 StringBuilder sb = new StringBuilder(multiplier * source.Length);
 for (int i = 0; i &lt; multiplier; i++)
 {
 sb.Append(source);
 }

 return sb.ToString();
}

string s = "&lt;/li&gt;&lt;/ul&gt;".Multiply(10);
</code></pre>

blocks|key|1628999|text|你必须编写一个方法--当然，对于C#+3.0，它可以是一个扩展方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1629000|public+static+string+Repeat(this+string,+int+count)+{
++++/*+StringBuilder+etc+*/+}|code-block|syntax|javascript|1629001|然后：|1629002|string+bar+=+"abc";
string+foo+=+bar.Repeat(2);|1629003|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|$]]

You'd have to write a method - of course, with C# 3.0 it could be an extension method:

<pre><code>public static string Repeat(this string, int count) {
 /* StringBuilder etc */ }
</code></pre>

then:

<pre><code>string bar = "abc";
string foo = bar.Repeat(2);
</code></pre>

blocks|key|1414273|text|string+Multiply(string+input,+int+times)
{
+++++StringBuilder+sb+=+new+StringBuilder(input.length+*+times);
+++++for+(int+i+=+0;+i+<+times;+i%2B%2B)
+++++{
++++++++++sb.Append(input);
+++++}
+++++return+sb.ToString();
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1414274|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>string Multiply(string input, int times)
{
 StringBuilder sb = new StringBuilder(input.length * times);
 for (int i = 0; i &lt; times; i++)
 {
 sb.Append(input);
 }
 return sb.ToString();
}
</code></pre>

blocks|key|1414359|text|I'm+with+DrJokepu+on+this+one，但是如果出于某种原因，你确实想使用内置功能作弊，那么你可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1414360|string+snip+=+"</li></ul>";
int+multiplier+=+2;

string+result+=+string.Join(snip,+new+string[multiplier+%2B+1]);|code-block|syntax|javascript|1414361|或者，如果您使用的是.NET+4：|1414362|string+result+=+string.Concat(Enumerable.Repeat(snip,+multiplier));|1414363|就我个人而言，我不会费心--定制的扩展方法要好得多。|1414364|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/532892/can-i-multiply-a-string-in-c/532912#532912^0|0|T|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|F|7|10|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|11|8|@]|9|@]|C|$]]|$1|K|3|L|5|F|7|12|8|@]|9|@]|C|$G|H]]|$1|M|3|N|5|6|7|13|8|@]|9|@]|C|$]]|$1|O|3|-4|5|6|7|14|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

<a href="https://stackoverflow.com/questions/532892/can-i-multiply-a-string-in-c/532912#532912">I'm with DrJokepu on this one</a>, but if for some reason you did want to cheat using built-in functionality then you could do something like this:

<pre><code>string snip = "&lt;/li&gt;&lt;/ul&gt;";
int multiplier = 2;

string result = string.Join(snip, new string[multiplier + 1]);
</code></pre>

Or, if you're using .NET 4:

<pre><code>string result = string.Concat(Enumerable.Repeat(snip, multiplier));
</code></pre>

Personally I wouldn't bother though - a custom extension method is much nicer.

blocks|key|1414445|text|好吧，这是我对这件事的看法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1414446|public+static+class+ExtensionMethods+{
++public+static+string+Multiply(this+string+text,+int+count)
++{
++++return+new+string(Enumerable.Repeat(text,+count)
++++++.SelectMany(s+=>+s.ToCharArray()).ToArray());
++}
}|code-block|syntax|javascript|1414447|当然，我有点傻，但是当我需要在代码生成类中使用制表时，Enumerable.Repeat会帮我做。是的，StringBuilder版本也很好。|1414448|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Okay, here's my take on the matter:

<pre><code>public static class ExtensionMethods {
 public static string Multiply(this string text, int count)
 {
 return new string(Enumerable.Repeat(text, count)
 .SelectMany(s =&gt; s.ToCharArray()).ToArray());
 }
}
</code></pre>

I'm being a bit silly of course, but when I need to have tabulation in code-generating classes, Enumerable.Repeat does it for me. And yeah, the StringBuilder version is fine, too.

blocks|key|1629266|text|请注意，如果您的"+string“只是一个字符，则有一个重载的string构造函数来处理它：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1629267|int+multipler+=+10;
string+TenAs+=+new+string+('A',+multipler);|code-block|syntax|javascript|1629268|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|$]]

Note that if your "string" is only a single character, there is an overload of the string constructor to handle it:

<pre><code>int multipler = 10;
string TenAs = new string ('A', multipler);
</code></pre>

blocks|key|1629310|text|为了完整起见--这是另一种方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1629311|public+static+string+Repeat(this+string+s,+int+count)
{
++++var+_s+=+new+System.Text.StringBuilder().Insert(0,+s,+count).ToString();
++++return+_s;
}|code-block|syntax|javascript|1629312|我想我前段时间从Stack+Overflow中删除了一个，所以这不是我的主意。|1629313|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Just for the sake of completeness - here is another way of doing this:

<pre><code>public static string Repeat(this string s, int count)
{
 var _s = new System.Text.StringBuilder().Insert(0, s, count).ToString();
 return _s;
}
</code></pre>

I think I pulled that one from Stack Overflow some time ago, so it is not my idea.

blocks|key|1414545|text|以下是我对此的看法，仅供将来参考：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1414546|++++///+<summary>
++++///+Repeats+a+System.String+instance+by+the+number+of+times+specified;
++++///+Each+copy+of+thisString+is+separated+by+a+separator
++++///+</summary>
++++///+<param+name="thisString">
++++///+The+current+string+to+be+repeated
++++///+</param>
++++///+<param+name="separator">
++++///+Separator+in+between+copies+of+thisString
++++///+</param>
++++///+<param+name="repeatTimes">
++++///+The+number+of+times+thisString+is+repeated</param>
++++///+<returns>
++++///+A+repeated+copy+of+thisString+by+repeatTimes+times+
++++///+and+separated+by+the+separator
++++///+</returns>
++++public+static+string+Repeat(this+string+thisString,+string+separator,+int+repeatTimes)+{
++++++++return+string.Join(separator,+ParallelEnumerable.Repeat(thisString,+repeatTimes));
++++}|code-block|syntax|javascript|1414547|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|$]]

Here's my take on this just for future reference:

<pre><code> /// &lt;summary&gt;
 /// Repeats a System.String instance by the number of times specified;
 /// Each copy of thisString is separated by a separator
 /// &lt;/summary&gt;
 /// &lt;param name="thisString"&gt;
 /// The current string to be repeated
 /// &lt;/param&gt;
 /// &lt;param name="separator"&gt;
 /// Separator in between copies of thisString
 /// &lt;/param&gt;
 /// &lt;param name="repeatTimes"&gt;
 /// The number of times thisString is repeated&lt;/param&gt;
 /// &lt;returns&gt;
 /// A repeated copy of thisString by repeatTimes times 
 /// and separated by the separator
 /// &lt;/returns&gt;
 public static string Repeat(this string thisString, string separator, int repeatTimes) {
 return string.Join(separator, ParallelEnumerable.Repeat(thisString, repeatTimes));
 }
</code></pre>

blocks|key|1414572|text|在.NET+4中，您可以执行以下操作：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1414573|String.Concat(Enumerable.Repeat("Hello",+4))|code-block|syntax|javascript|1414574|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|$]]

In .NET 4 you can do this:

<pre><code>String.Concat(Enumerable.Repeat("Hello", 4))
</code></pre>

blocks|key|1629443|text|如果你有.Net+3.5而不是4.0，你可以使用System.Linq的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1629444|String.Concat(Enumerable.Range(0,+4).Select(_+=>+"Hello").ToArray())|code-block|syntax|javascript|1629445|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|$]]

If you have .Net 3.5 but not 4.0, you can use System.Linq's

<pre><code>String.Concat(Enumerable.Range(0, 4).Select(_ =&gt; "Hello").ToArray())
</code></pre>

blocks|key|1414656|text|既然每个人都在添加自己的.NET4/Linq示例，我不妨添加自己的示例。(基本上，it+DrJokepu's，简化为一行)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1414657|public+static+string+Multiply(this+string+source,+int+multiplier)+
{+
++++return+Enumerable.Range(1,multiplier)
+++++++++++++.Aggregate(new+StringBuilder(multiplier*source.Length),+
+++++++++++++++++++(sb,+n)=>sb.Append(source))
+++++++++++++.ToString();
}|code-block|syntax|javascript|1414658|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|$]]

Since everyone is adding their own .NET4/Linq examples, I might as well add my own. (Basically, it DrJokepu's, reduced to a one-liner)

<pre><code>public static string Multiply(this string source, int multiplier) 
{ 
 return Enumerable.Range(1,multiplier)
 .Aggregate(new StringBuilder(multiplier*source.Length), 
 (sb, n)=&gt;sb.Append(source))
 .ToString();
}
</code></pre>

blocks|key|1414676|text|这要简洁得多：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1414677|new+StringBuilder().Insert(0,+"</li></ul>",+count).ToString()|code-block|syntax|javascript|1414678|在这种情况下，应该导入名称空间using+System.Text;。|offset|length|style|CODE|1414679|entityMap^0|0|0|F|I|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]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

This is a lot more concise: 

<pre><code>new StringBuilder().Insert(0, "&lt;/li&gt;&lt;/ul&gt;", count).ToString()
</code></pre>

The namespace <code>using System.Text;</code> should be imported in this case.

Suppose I have a string, for example,

<pre><code>string snip = "&lt;/li&gt;&lt;/ul&gt;";
</code></pre>

I want to basically write it multiple times, depending on some integer value. 

<pre><code>string snip = "&lt;/li&gt;&lt;/ul&gt;";
int multiplier = 2;

// TODO: magic code to do this 
// snip * multiplier = "&lt;/li&gt;&lt;/ul&gt;&lt;/li&gt;&lt;/ul&gt;";
</code></pre>

EDIT:
I know I can easily write my own function to implement this, I was just wondering if there was some weird string operator that I didn't know about

Can I "multiply" a string (in C#)?

假设我有一个字符串，例如，string snip = "</li></ul>";我想要根据一些整数值，多次写入它。string snip = "</li></ul>";int multiplier = 2;// TODO: magic code to do this // snip * multiplier = "...

问我可以“乘”一个字符串(在C#中)吗？
EN

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问我可以“乘”一个字符串(在C#中)吗？
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