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Question

我正在输出给定字符串关键字的搜索结果列表，我希望我的搜索结果中的任何匹配关键字都会突出显示。每个单词应包含在跨度或类似内容中。我正在寻找一种有效的功能来实现这一目标。

E.g。

关键词：“lorem ipsum”

结果：“一些包含lorem和ipsum的文本”

所需的HTML输出：“Some text containing <span class="hit">lorem</span> and <span class="hit">ipsum</span>”

我的结果不区分大小写。

Answer 1

这是我决定的。我可以在页面/页面部分的相关字符串上调用扩展函数：

public static string HighlightKeywords(this string input, string keywords)
{
    if (input == string.Empty || keywords == string.Empty)
    {
        return input;
    }

    string[] sKeywords = keywords.Split(' ');
    foreach (string sKeyword in sKeywords)
    {
        try
        {
            input = Regex.Replace(input, sKeyword, string.Format("<span class=\"hit\">{0}</span>", "$0"), RegexOptions.IgnoreCase);
        }
        catch
        {
            //
        }
    }
    return input;
}

还有其他建议或意见吗？

Answer 2

尝试使用Lucene.net的荧光笔

http://incubator.apache.org/lucene.net/docs/2.0/Highlighter.Net/Lucene.Net.Highlight.html

使用方法：

http://davidpodhola.blogspot.com/2008/02/how-to-highlight-phrase-on-results-from.html

编辑：只要Lucene.net荧光笔不适合这里的新链接：

http://mhinze.com/archive/search-term-highlighter-httpmodule/

Answer 3

使用jquery高亮插件。

在服务器端突出显示

protected override void Render( HtmlTextWriter writer )
{
    StringBuilder html = new StringBuilder();
    HtmlTextWriter w = new HtmlTextWriter( new StringWriter( html ) );

    base.Render( w );

    html.Replace( "lorem", "<span class=\"hit\">lorem</span>" );

    writer.Write( html.ToString() );
}

您可以使用正则表达式替换高级文本。

您还可以在HttpModule中编写上述代码，以便在其他应用程序中重复使用。

Answer 4

我在ASP.NET中有类似的要求。这是我用C＃编写的高亮关键字解决方案。

Algo使用的是朴素搜索算法。

维护一个哈希表以存储匹配项。

在有关键字匹配的字符串上应用标记。

区域突出显示

    /// <summary>
    /// Higlight the search term.
    /// </summary>
    /// <param name="currentString"></param>
    /// <returns></returns>
    private string Highlight(string currentString)
    {
        try
        {
            var termValue = _helperRequest.SearchText;
            if (!string.IsNullOrEmpty(currentString) && !string.IsNullOrEmpty(termValue))
            {
                currentString = termValue.Trim().Split(Constants.Separator)
                                                .ToList().Where(x => x.Length >1)
                                                .Distinct()
                                                .OrderByDescending(x => x.Length)
                                                .Aggregate(currentString, (current, keyWord) =>
                                                 TagIndexers(new SearchHelperRequest() { SearchString = current, SearchTerm = keyWord, HightlightCss = _helperRequest.HightlightCss, Comparison = StringComparison.InvariantCultureIgnoreCase, TagIdentifier = GetRandomKey() }));
            }
        }
        catch (Exception ex)
        {
            Logger.WriteError(string.Format("Highlight Error : {0}", ex.Message));
        }
        finally
        {
            //Replace tags with highlight terms.
            if (_helperRequest != null)
            {
                if (_helperRequest.TagKeyLookup.Keys.Count > 0)
                {
                    foreach (string tagKey in _helperRequest.TagKeyLookup.Keys)
                    {
                        if (!string.IsNullOrEmpty(currentString))
                            currentString = currentString.Replace(tagKey, _helperRequest.TagKeyLookup[tagKey]);
                    }

                    //clear the key list.
                    _helperRequest.TagKeyLookup.Clear();
                }
            }
        }
        return HttpUtility.JavaScriptStringEncode(currentString);
    }
    /// <summary>
    /// Generate a randome key from lookup table. Recurrsive in  nature.
    /// </summary>
    /// <returns></returns>
    private string GetRandomKey()
    {
        //config your key length
        var charBuffer = new char[4];
        lock (charBuffer)
        {
            for (var iCounter = 0; iCounter < charBuffer.Length; iCounter++)
            {
                charBuffer[iCounter] = CharacterLookup
                    [new Random().Next(CharacterLookup.Length)];
            }
        }
        //Recurssion to generate random.
        return _helperRequest.TagKeyLookup.
            ContainsKey(new String(charBuffer))
            ? GetRandomKey() : new String(charBuffer);
    }
    /// <summary>
    /// Replace the term with identifiers
    /// </summary>
    /// <param name="searchRequest"></param>
    /// <returns></returns>
    private string TagIndexers(SearchHelperRequest searchRequest)
    {
        try
        {
            var highlightBulder = new StringBuilder();
            string spanValue = string.Empty;
            if (!string.IsNullOrEmpty(searchRequest.SearchString) && !string.IsNullOrEmpty(searchRequest.SearchTerm))
            {
                int previousIndex = 0;
                int currentIndex = searchRequest.SearchString.IndexOf(searchRequest.SearchTerm, searchRequest.Comparison);
                while (currentIndex != -1)
                {
                    highlightBulder.Append(searchRequest.SearchString.Substring(previousIndex, currentIndex - previousIndex));
                    spanValue = string.Format(searchRequest.HightlightCss, searchRequest.SearchString.Substring(currentIndex, searchRequest.SearchTerm.Length));
                    highlightBulder.Append(searchRequest.TagIdentifier);
                    currentIndex += searchRequest.SearchTerm.Length;
                    previousIndex = currentIndex;
                    currentIndex = searchRequest.SearchString.IndexOf(searchRequest.SearchTerm, currentIndex, searchRequest.Comparison);
                }
                if (!_helperRequest.TagKeyLookup.ContainsKey(searchRequest.TagIdentifier) &&
                    !string.IsNullOrEmpty(spanValue))
                {
                    _helperRequest.TagKeyLookup.Add(searchRequest.TagIdentifier, spanValue);
                }
                highlightBulder.Append(searchRequest.SearchString.Substring(previousIndex));
            }
            return highlightBulder.ToString();
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    #endregion
private static char[] _characterLookup = null;
    public char[] CharacterLookup
    {
        get
        {
            if (_characterLookup == null)
            {
                _characterLookup = new char[36];

                lock (_characterLookup)
                {
                    int indexer = 0;
                    //build the table.
                    for (char c = '0'; c <= '9'; c++) _characterLookup[indexer++] = c;
                    for (char c = 'A'; c <= 'Z'; c++) _characterLookup[indexer++] = c;
                }
            }
            return _characterLookup;
        }
    }

**例程摘要：

搜索字词并应用标记。
将唯一标记存储在哈希表中。
用Span Highlights替换标签。**

Answer 5

上述答案的扩展。（没有足够的声誉来发表评论）

为了避免在搜索条件为[span pan a a]时替换范围，找到的单词被替换为除了替换之外的其他内容......虽然效率不高......

public string Highlight(string input)
{
    if (input == string.Empty || searchQuery == string.Empty)
    {
        return input;
    }

    string[] sKeywords = searchQuery.Replace("~",String.Empty).Replace("  "," ").Trim().Split(' ');
    int totalCount = sKeywords.Length + 1;
    string[] sHighlights = new string[totalCount];
    int count = 0;

    input = Regex.Replace(input, Regex.Escape(searchQuery.Trim()), string.Format("~{0}~", count), RegexOptions.IgnoreCase);
    sHighlights[count] = string.Format("<span class=\"highlight\">{0}</span>", searchQuery);
    foreach (string sKeyword in sKeywords.OrderByDescending(s => s.Length))
    {
        count++;
        input = Regex.Replace(input, Regex.Escape(sKeyword), string.Format("~{0}~", count), RegexOptions.IgnoreCase);
        sHighlights[count] = string.Format("<span class=\"highlight\">{0}</span>", sKeyword);
    }

    for (int i = totalCount - 1; i >= 0; i--)
    {
        input = Regex.Replace(input, "\\~" + i + "\\~", sHighlights[i], RegexOptions.IgnoreCase);
    }

    return input;
}

在ASP.Net中搜索关键字高亮显示

5 个答案:

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