8

我试图在 Umbraco 中实现省略号,要求是 15 个字符的介绍文本,但总是以一个完整的单词结尾。

我曾想过使用 XSLT,但后来意识到我可以使用用 C# 编写的简单扩展方法。

我可以轻松地对文本进行子串化并附加“...”,但我遇到了不得不用一个完整的单词结束它的问题。这是我到目前为止的代码(非常复杂:p)

public string Ellipsis(string text, int length)
{
    return text.Substring(0, length) + "...";
}

示例文本

Lorem ipsum dolor 坐在 amet,amet consectetur adipiscing elit。

如果我们实现上面的省略号方法(长度 = 15),输出将如下所示

Lorem ipsum dolor sit amet, amet consectetur adipi...

我想确保没有单词被切片,所以输出应该看起来像

Lorem ipsum dolor 坐 amet,amet consectetur adipiscing

任何帮助表示赞赏。

编辑

运行以下代码的示例后,如果省略号长度以最后一个单词结尾,则根本不会显示任何文本。

这是输出,见第 56-60 行

0 : Lorem...
1 : Lorem...
2 : Lorem...
3 : Lorem...
4 : Lorem...
5 : Lorem...
6 : Lorem ipsum...
7 : Lorem ipsum...
8 : Lorem ipsum...
9 : Lorem ipsum...
10 : Lorem ipsum...
11 : Lorem ipsum...
12 : Lorem ipsum dolor...
13 : Lorem ipsum dolor...
14 : Lorem ipsum dolor...
15 : Lorem ipsum dolor...
16 : Lorem ipsum dolor...
17 : Lorem ipsum dolor...
18 : Lorem ipsum dolor sit...
19 : Lorem ipsum dolor sit...
20 : Lorem ipsum dolor sit...
21 : Lorem ipsum dolor sit...
22 : Lorem ipsum dolor sit amet,...
23 : Lorem ipsum dolor sit amet,...
24 : Lorem ipsum dolor sit amet,...
25 : Lorem ipsum dolor sit amet,...
26 : Lorem ipsum dolor sit amet,...
27 : Lorem ipsum dolor sit amet,...
28 : Lorem ipsum dolor sit amet, amet...
29 : Lorem ipsum dolor sit amet, amet...
30 : Lorem ipsum dolor sit amet, amet...
31 : Lorem ipsum dolor sit amet, amet...
32 : Lorem ipsum dolor sit amet, amet...
33 : Lorem ipsum dolor sit amet, amet consectetur...
34 : Lorem ipsum dolor sit amet, amet consectetur...
35 : Lorem ipsum dolor sit amet, amet consectetur...
36 : Lorem ipsum dolor sit amet, amet consectetur...
37 : Lorem ipsum dolor sit amet, amet consectetur...
38 : Lorem ipsum dolor sit amet, amet consectetur...
39 : Lorem ipsum dolor sit amet, amet consectetur...
40 : Lorem ipsum dolor sit amet, amet consectetur...
41 : Lorem ipsum dolor sit amet, amet consectetur...
42 : Lorem ipsum dolor sit amet, amet consectetur...
43 : Lorem ipsum dolor sit amet, amet consectetur...
44 : Lorem ipsum dolor sit amet, amet consectetur...
45 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
46 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
47 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
48 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
49 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
50 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
51 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
52 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
53 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
54 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
55 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
56 : ...
57 : ...
58 : ...
59 : ...
60 : ...
61 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
62 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
63 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
64 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
65 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
66 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
67 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
68 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
69 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
70 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
71 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
72 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
73 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
74 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
75 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
76 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
77 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
78 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
79 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.

马尔科

4

2 回答 2

20
if (text.Length <= length) return text;
int pos = text.IndexOf(" ", length) ;
if (pos >= 0)
    return text.Substring(0, pos) + "...";
return text;

编辑:这是我测试过的程序:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1 {
    class Program {
        static void Main(string[] args) {
            for (int i = 0; i < 40; ++i) {
                string s = Ellipsis("Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.", i);
                Console.WriteLine("{0} : {1}", i, s);
            }
        }

        static public string Ellipsis(string text, int length) {
          if (text.Length <= length) return text;
          int pos = text.IndexOf(" ", length) ;
          if (pos >= 0)
            return text.Substring(0, pos) + "...";
          return text;
        }
    }
}

这是输出:

0 : Lorem...
1 : Lorem...
2 : Lorem...
3 : Lorem...
4 : Lorem...
5 : Lorem...
6 : Lorem ipsum...
7 : Lorem ipsum...
8 : Lorem ipsum...
9 : Lorem ipsum...
10 : Lorem ipsum...
11 : Lorem ipsum...
12 : Lorem ipsum dolor...
13 : Lorem ipsum dolor...
14 : Lorem ipsum dolor...
15 : Lorem ipsum dolor...
16 : Lorem ipsum dolor...
17 : Lorem ipsum dolor...
18 : Lorem ipsum dolor sit...
19 : Lorem ipsum dolor sit...
20 : Lorem ipsum dolor sit...
21 : Lorem ipsum dolor sit...
22 : Lorem ipsum dolor sit amet,...
23 : Lorem ipsum dolor sit amet,...
24 : Lorem ipsum dolor sit amet,...
25 : Lorem ipsum dolor sit amet,...
26 : Lorem ipsum dolor sit amet,...
27 : Lorem ipsum dolor sit amet,...
28 : Lorem ipsum dolor sit amet, amet...
29 : Lorem ipsum dolor sit amet, amet...
30 : Lorem ipsum dolor sit amet, amet...
31 : Lorem ipsum dolor sit amet, amet...
32 : Lorem ipsum dolor sit amet, amet...
33 : Lorem ipsum dolor sit amet, amet consectetur...
34 : Lorem ipsum dolor sit amet, amet consectetur...
35 : Lorem ipsum dolor sit amet, amet consectetur...
36 : Lorem ipsum dolor sit amet, amet consectetur...
37 : Lorem ipsum dolor sit amet, amet consectetur...
38 : Lorem ipsum dolor sit amet, amet consectetur...
39 : Lorem ipsum dolor sit amet, amet consectetur...
于 2010-09-27T03:45:40.493 回答
3

我想给出一个替代实现,因为 Preet 给出的代码不能确保最大文本长度。我必须实现一个单词省略号函数,该函数返回一个硬长度限制的文本单词省略号修剪。此外,在省略号之前也会修剪标点符号。

public class WordProcessing
{
    static public string WordEllipsis(string text, int maxLength, string ellipsis = "...")
    {
        string result;

        if (text.Length <= maxLength)
        {
            result = text;
        }
        else if (maxLength <= ellipsis.Length)
        {
            result = ellipsis.Substring(0, maxLength);
        }
        else
        {
            result = text.Substring(0, maxLength - ellipsis.Length);
            var lastWordPosition = result.LastIndexOf(' ');

            if (lastWordPosition < 0)
            {
                lastWordPosition = 0;
            }
            result = result.Substring(0, lastWordPosition).Trim(new[] { '.', ',', '!', '?' }) + ellipsis;
        }

        return result;
    }
}

单元测试 - 就像一个魅力。

输出:

0 : 
1 : .
2 : ..
3 : ...
4 : ...
5 : ...
6 : ...
7 : ...
8 : ...
9 : Lorem...
10 : Lorem...
11 : Lorem...
12 : Lorem...
13 : Lorem...
14 : Lorem...
15 : Lorem ipsum...
16 : Lorem ipsum...
17 : Lorem ipsum...
18 : Lorem ipsum...
19 : Lorem ipsum...
20 : Lorem ipsum...
21 : Lorem ipsum dolor...
22 : Lorem ipsum dolor...
23 : Lorem ipsum dolor...
24 : Lorem ipsum dolor...
25 : Lorem ipsum dolor sit...
26 : Lorem ipsum dolor sit...
27 : Lorem ipsum dolor sit...
28 : Lorem ipsum dolor sit...
29 : Lorem ipsum dolor sit...
30 : Lorem ipsum dolor sit...
31 : Lorem ipsum dolor sit amet...
32 : Lorem ipsum dolor sit amet...
33 : Lorem ipsum dolor sit amet...
34 : Lorem ipsum dolor sit amet...
35 : Lorem ipsum dolor sit amet...
36 : Lorem ipsum dolor sit amet, amet...
37 : Lorem ipsum dolor sit amet, amet...
38 : Lorem ipsum dolor sit amet, amet...
39 : Lorem ipsum dolor sit amet, amet...
40 : Lorem ipsum dolor sit amet, amet...
41 : Lorem ipsum dolor sit amet, amet...
42 : Lorem ipsum dolor sit amet, amet...
43 : Lorem ipsum dolor sit amet, amet...
44 : Lorem ipsum dolor sit amet, amet...
45 : Lorem ipsum dolor sit amet, amet...
46 : Lorem ipsum dolor sit amet, amet...
47 : Lorem ipsum dolor sit amet, amet...
48 : Lorem ipsum dolor sit amet, amet consectetur...
49 : Lorem ipsum dolor sit amet, amet consectetur...
50 : Lorem ipsum dolor sit amet, amet consectetur...
51 : Lorem ipsum dolor sit amet, amet consectetur...
52 : Lorem ipsum dolor sit amet, amet consectetur...
53 : Lorem ipsum dolor sit amet, amet consectetur...
54 : Lorem ipsum dolor sit amet, amet consectetur...
55 : Lorem ipsum dolor sit amet, amet consectetur...
56 : Lorem ipsum dolor sit amet, amet consectetur...
57 : Lorem ipsum dolor sit amet, amet consectetur...
58 : Lorem ipsum dolor sit amet, amet consectetur...
59 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
60 : Lorem ipsum dolor sit amet, amet consectetur adipiscing...
61 : Lorem ipsum dolor sit amet, amet consectetur adipiscing elit.
于 2013-02-13T09:18:56.290 回答