blocks|key|620969|text|下面是封装在扩展方法中的逻辑：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|620970|public+static+string+Truncate(this+string+value,+int+maxChars)
{
++++return+value.Length+<=+maxChars+?+value+:+value.Substring(0,+maxChars)+%2B+"...";
}|code-block|syntax|javascript|620971|用法：|620972|var+s+=+"abcdefg";

Console.WriteLine(s.Truncate(3));|620973|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|$]]

Here is the logic wrapped up in an extension method:

<pre><code>public static string Truncate(this string value, int maxChars)
{
 return value.Length &lt;= maxChars ? value : value.Substring(0, maxChars) + "...";
}
</code></pre>

Usage:

<pre><code>var s = "abcdefg";

Console.WriteLine(s.Truncate(3));
</code></pre>

blocks|key|837031|text|都是非常好的答案，但为了把它弄清楚一点，如果你的字符串是句子，不要在单词中间打断你的字符串。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|837032|private+string+TruncateForDisplay(this+string+value,+int+length)
{
++if+(string.IsNullOrEmpty(value))+return+string.Empty;
++var+returnValue+=+value;
++if+(value.Length+>+length)
++{
++++var+tmp+=+value.Substring(0,+length)+;
++++if+(tmp.LastIndexOf('+')+>+0)
+++++++returnValue+=+tmp.Substring(0,+tmp.LastIndexOf('+')+)+%2B+"+...";
++}++++++++++++++++
++return+returnValue;
}|code-block|syntax|javascript|837033|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|$]]

All very good answers, but to clean it up just a little, if your strings are sentences, don't break your string in the middle of a word.

<pre><code>private string TruncateForDisplay(this string value, int length)
{
 if (string.IsNullOrEmpty(value)) return string.Empty;
 var returnValue = value;
 if (value.Length &gt; length)
 {
 var tmp = value.Substring(0, length) ;
 if (tmp.LastIndexOf(' ') &gt; 0)
 returnValue = tmp.Substring(0, tmp.LastIndexOf(' ') ) + " ...";
 } 
 return returnValue;
}
</code></pre>

blocks|key|836557|text|public+string+TruncString(string+myStr,+int+THRESHOLD)
{
++++if+(myStr.Length+>+THRESHOLD)
++++++++return+myStr.Substring(0,+THRESHOLD)+%2B+"...";
++++return+myStr;
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|836558|忽略命名约定，以防他真的需要阈值变量，或者它总是相同的大小。|unstyled|836559|另一个选择|836560|string+res+=+(myStr.Length+>+THRESHOLD)+?+myStr.Substring(0,+THRESHOLD)+%2B+".."+:+myStr;|836561|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|N|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$B|C]]|$1|K|3|-4|5|F|7|Q|8|@]|9|@]|A|$]]]|L|$]]

<pre><code>public string TruncString(string myStr, int THRESHOLD)
{
 if (myStr.Length &gt; THRESHOLD)
 return myStr.Substring(0, THRESHOLD) + "...";
 return myStr;
}
</code></pre>

Ignore the naming convention it's just in case he actually needs the THRESHOLD variable or if it's always the same size.

Alternatively

<pre><code>string res = (myStr.Length &gt; THRESHOLD) ? myStr.Substring(0, THRESHOLD) + ".." : myStr;
</code></pre>

blocks|key|621006|text|这是一个解释椭圆长度的版本：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|621007|++++public+static+string+Truncate(this+string+value,+int+maxChars)
++++{
++++++++const+string+ellipses+=+"...";
++++++++return+value.Length+<=+maxChars+?+value+:+value.Substring(0,+maxChars+-+ellipses.Length)+%2B+ellipses;
++++}|code-block|syntax|javascript|621008|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 a version that accounts for the length of the ellipses: 

<pre><code> public static string Truncate(this string value, int maxChars)
 {
 const string ellipses = "...";
 return value.Length &lt;= maxChars ? value : value.Substring(0, maxChars - ellipses.Length) + ellipses;
 }
</code></pre>

blocks|key|620769|text|代码隐藏：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|620770|string+shorten(sting+s)
{
++++//string+s+=+abcdefg;
++++int+tooLongInt+=+3;

++++if+(s.Length+>+tooLongInt)
++++++++return+s.Substring(0,+tooLongInt)+%2B+"..";

++++return+s;
}|code-block|syntax|javascript|620771|标记：|620772|<td><%25=+shorten(YOUR_STRING_HERE)+%25></td>|620773|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|$]]

Code behind:

<pre><code>string shorten(sting s)
{
 //string s = abcdefg;
 int tooLongInt = 3;

 if (s.Length &gt; tooLongInt)
 return s.Substring(0, tooLongInt) + "..";

 return s;
}
</code></pre>

Markup:

<pre><code>&lt;td&gt;&lt;%= shorten(YOUR_STRING_HERE) %&gt;&lt;/td&gt;
</code></pre>

blocks|key|836612|text|也许为此目的实现一个方法会更好：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|836613|string+shorten(sting+yourStr)
{
//Suppose+you+have+a+string+yourStr,+toView+and+a+constant+value+

++++string+toView;
++++const+int+maxView+=+3;

++++if+(yourStr.Length+>+maxView)
++++++++toView+=+yourStr.Substring(0,+maxView)+%2B+"+...";+//+all+you+have+is+to+use+Substring(int,+int)+.net+method
++++else
++++++++toView+=+yourStr;
return+toView;
}|code-block|syntax|javascript|836614|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|$]]

Maybe it is better to implement a method for that purpose:

<pre><code>string shorten(sting yourStr)
{
//Suppose you have a string yourStr, toView and a constant value 

 string toView;
 const int maxView = 3;

 if (yourStr.Length &gt; maxView)
 toView = yourStr.Substring(0, maxView) + " ..."; // all you have is to use Substring(int, int) .net method
 else
 toView = yourStr;
return toView;
}
</code></pre>

blocks|key|620877|text|string+s+=+"abcdefg";
if+(s.length+>+3)
{
++++s+=+s.substring(0,3);
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|620878|您可以使用Substring函数。|unstyled|620879|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>string s = "abcdefg";
if (s.length &gt; 3)
{
 s = s.substring(0,3);
}
</code></pre>

You can use the Substring function.

blocks|key|620925|text|当然，下面是一些示例代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|620926|string+str+=+"abcdefg";
if+(str.Length+>+X){
+++str+=+str.Substring(0,+X)+%2B+"...";
}|code-block|syntax|javascript|620927|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|$]]

Sure, here is some sample code:

<pre><code>string str = "abcdefg";
if (str.Length &gt; X){
 str = str.Substring(0, X) + "...";
}
</code></pre>

blocks|key|836976|text|我最近遇到了这个问题。我在一个4000个字符的nvarcharMAX+DB字段中存储了一条“状态”消息。然而，我的状态消息正在堆积，并遇到了异常。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|836977|但这不是一个简单的截断情况，因为任意截断会孤立状态消息的一部分，所以我真的需要在字符串的一致部分进行“截断”。|836978|我解决了这个问题，将字符串转换为字符串数组，删除第一个元素，然后恢复为字符串。下面是代码("CurrentStatus“是保存数据的字符串)……|836979|++++++++if+(CurrentStatus.Length+>=+3750)
++++++++{
++++++++++++//+perform+some+truncation+to+free+up+some+space.

++++++++++++//+Lets+get+the+status+messages+into+an+array+for+processing...
++++++++++++//+We+use+the+period+as+the+delimiter,+then+skip+the+first+item+and+re-insert+into+an+array.

++++++++++++string[]+statusArray+=+CurrentStatus.Split(new+string[]+{+"."+},+StringSplitOptions.None)
++++++++++++++++++++++++++++++++++++.Skip(1).ToArray();

++++++++++++//+Next+we+return+the+data+to+a+string+and+replace+any+escaped+returns+with+proper+one.
++++++++++++CurrentStatus+=+(string.Join(".",+statusArray))
++++++++++++++++++++++++++++++++++++.Replace("\\r\\n",+Environment.NewLine);


++++++++}|code-block|syntax|javascript|836980|希望这能帮助到某个人。|836981|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|Q|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|R|8|@]|9|@]|A|$I|J]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

I has this problem recently. I was storing a "status" message in a nvarcharMAX DB field which is 4000 characters. However my status messages were building up and hitting the exception. 

But it wasn't a simple case of truncation as an arbitrary truncation would orphan part of a status message, so I really needed to "truncate" at a consistent part of the string. 

I solved the problem by converting the string to a string array, removing the first element and then restoring to a string. Here is the code ("CurrentStatus" is the string holding the data)...

<pre><code> if (CurrentStatus.Length &gt;= 3750)
 {
 // perform some truncation to free up some space.

 // Lets get the status messages into an array for processing...
 // We use the period as the delimiter, then skip the first item and re-insert into an array.

 string[] statusArray = CurrentStatus.Split(new string[] { "." }, StringSplitOptions.None)
 .Skip(1).ToArray();

 // Next we return the data to a string and replace any escaped returns with proper one.
 CurrentStatus = (string.Join(".", statusArray))
 .Replace("\\r\\n", Environment.NewLine);


 }
</code></pre>

Hope it helps someone out.

Hope somebody has a good idea. I have strings like this:

<pre><code>abcdefg
abcde
abc
</code></pre>

What I need is for them to be trucated to show like this if more than a specified lenght:

<pre><code>abc ..
abc ..
abc
</code></pre>

Is there any simple C# code I can use for this?

How can I truncate my strings with a "..." if they are too long?

希望有人有个好主意。我有这样的字符串：abcdefgabcdeabc我需要的是让它们在超过指定长度的情况下像这样显示：abc ..abc ..abc有没有什么简单的C#代码可以用来做这件事？

问如何使用"...“截断字符串？如果它们太长了呢？
EN

回答 9

Stack Overflow用户

Stack Overflow用户

Stack Overflow用户

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问如何使用"...“截断字符串？如果它们太长了呢？EN

回答 9

Stack Overflow用户

Stack Overflow用户

Stack Overflow用户

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问如何使用"...“截断字符串？如果它们太长了呢？
EN