什么是一个好的完整正则表达式或其他一些过程,将采取标题:

如何将标题更改为URL的一部分,如堆栈溢出?

然后把它变成

how-do-you-change-a-title-to-be-part-of-the-url-like-stack-overflow

在堆栈溢出的seo友好的url中使用?

我使用的开发环境是Ruby on Rails,但是如果有一些其他特定于平台的解决方案(。NET, PHP, Django),我也很想看到这些。

我相信我(或其他读者)在不同的平台上也会遇到同样的问题。

我使用自定义路由,我主要想知道如何改变字符串的所有特殊字符被删除,它都是小写的,所有空白被替换。


当前回答

我不太了解Ruby或Rails,但在Perl中,这是我要做的:

my $title = "How do you change a title to be part of the url like Stackoverflow?";

my $url = lc $title;   # Change to lower case and copy to URL.
$url =~ s/^\s+//g;     # Remove leading spaces.
$url =~ s/\s+$//g;     # Remove trailing spaces.
$url =~ s/\s+/\-/g;    # Change one or more spaces to single hyphen.
$url =~ s/[^\w\-]//g;  # Remove any non-word characters.

print "$title\n$url\n";

我刚做了一个快速测试,似乎有用。希望这在Ruby中比较容易翻译。

其他回答

有一个叫PermalinkFu的小Ruby on Rails插件可以做到这一点。escape方法将转换为适合URL的字符串。看一下代码;那个方法很简单。

为了删除非ascii字符,它使用iconv lib将'utf-8'转换为'ascii//ignore//translit'。然后空格变成破折号,所有东西都被缩小,等等。

我们是这样做的。注意,可能有比你第一眼意识到的更多的边缘条件。

这是第二个版本,展开后的性能提高了5倍(是的,我对它进行了基准测试)。我认为我应该优化它,因为这个函数可以在每页被调用数百次。

/// <summary>
/// Produces optional, URL-friendly version of a title, "like-this-one". 
/// hand-tuned for speed, reflects performance refactoring contributed
/// by John Gietzen (user otac0n) 
/// </summary>
public static string URLFriendly(string title)
{
    if (title == null) return "";

    const int maxlen = 80;
    int len = title.Length;
    bool prevdash = false;
    var sb = new StringBuilder(len);
    char c;

    for (int i = 0; i < len; i++)
    {
        c = title[i];
        if ((c >= 'a' && c <= 'z') || (c >= '0' && c <= '9'))
        {
            sb.Append(c);
            prevdash = false;
        }
        else if (c >= 'A' && c <= 'Z')
        {
            // tricky way to convert to lowercase
            sb.Append((char)(c | 32));
            prevdash = false;
        }
        else if (c == ' ' || c == ',' || c == '.' || c == '/' || 
            c == '\\' || c == '-' || c == '_' || c == '=')
        {
            if (!prevdash && sb.Length > 0)
            {
                sb.Append('-');
                prevdash = true;
            }
        }
        else if ((int)c >= 128)
        {
            int prevlen = sb.Length;
            sb.Append(RemapInternationalCharToAscii(c));
            if (prevlen != sb.Length) prevdash = false;
        }
        if (i == maxlen) break;
    }

    if (prevdash)
        return sb.ToString().Substring(0, sb.Length - 1);
    else
        return sb.ToString();
}

要查看被替换的代码的前一个版本(但在功能上与之相当,而且快了5倍),请查看这篇文章的修订历史(单击日期链接)。

另外,RemapInternationalCharToAscii方法的源代码可以在这里找到。

您可以使用以下帮助器方法。它可以转换Unicode字符。

public static string ConvertTextToSlug(string s)
{
    StringBuilder sb = new StringBuilder();

    bool wasHyphen = true;

    foreach (char c in s)
    {
        if (char.IsLetterOrDigit(c))
        {
            sb.Append(char.ToLower(c));
            wasHyphen = false;
        }
        else
            if (char.IsWhiteSpace(c) && !wasHyphen)
            {
                sb.Append('-');
                wasHyphen = true;
            }
    }

    // Avoid trailing hyphens
    if (wasHyphen && sb.Length > 0)
        sb.Length--;

    return sb.ToString().Replace("--","-");
}

你也可以使用这个JavaScript函数在表单中生成鼻涕虫(这个是基于/从Django复制的):

function makeSlug(urlString, filter) {
    // Changes, e.g., "Petty theft" to "petty_theft".
    // Remove all these words from the string before URLifying

    if(filter) {
        removelist = ["a", "an", "as", "at", "before", "but", "by", "for", "from",
        "is", "in", "into", "like", "of", "off", "on", "onto", "per",
        "since", "than", "the", "this", "that", "to", "up", "via", "het", "de", "een", "en",
        "with"];
    }
    else {
        removelist = [];
    }
    s = urlString;
    r = new RegExp('\\b(' + removelist.join('|') + ')\\b', 'gi');
    s = s.replace(r, '');
    s = s.replace(/[^-\w\s]/g, ''); // Remove unneeded characters
    s = s.replace(/^\s+|\s+$/g, ''); // Trim leading/trailing spaces
    s = s.replace(/[-\s]+/g, '-'); // Convert spaces to hyphens
    s = s.toLowerCase(); // Convert to lowercase
    return s; // Trim to first num_chars characters
}

我将代码移植到TypeScript中。它可以很容易地适应JavaScript。

我添加了一个.contains方法到字符串原型,如果你的目标是最新的浏览器或ES6,你可以使用.includes代替。

if (!String.prototype.contains) {
    String.prototype.contains = function (check) {
        return this.indexOf(check, 0) !== -1;
    };
}

declare interface String {
    contains(check: string): boolean;
}

export function MakeUrlFriendly(title: string) {
            if (title == null || title == '')
                return '';

            const maxlen = 80;
            let len = title.length;
            let prevdash = false;
            let result = '';
            let c: string;
            let cc: number;
            let remapInternationalCharToAscii = function (c: string) {
                let s = c.toLowerCase();
                if ("àåáâäãåą".contains(s)) {
                    return "a";
                }
                else if ("èéêëę".contains(s)) {
                    return "e";
                }
                else if ("ìíîïı".contains(s)) {
                    return "i";
                }
                else if ("òóôõöøőð".contains(s)) {
                    return "o";
                }
                else if ("ùúûüŭů".contains(s)) {
                    return "u";
                }
                else if ("çćčĉ".contains(s)) {
                    return "c";
                }
                else if ("żźž".contains(s)) {
                    return "z";
                }
                else if ("śşšŝ".contains(s)) {
                    return "s";
                }
                else if ("ñń".contains(s)) {
                    return "n";
                }
                else if ("ýÿ".contains(s)) {
                    return "y";
                }
                else if ("ğĝ".contains(s)) {
                    return "g";
                }
                else if (c == 'ř') {
                    return "r";
                }
                else if (c == 'ł') {
                    return "l";
                }
                else if (c == 'đ') {
                    return "d";
                }
                else if (c == 'ß') {
                    return "ss";
                }
                else if (c == 'Þ') {
                    return "th";
                }
                else if (c == 'ĥ') {
                    return "h";
                }
                else if (c == 'ĵ') {
                    return "j";
                }
                else {
                    return "";
                }
            };

            for (let i = 0; i < len; i++) {
                c = title[i];
                cc = c.charCodeAt(0);

                if ((cc >= 97 /* a */ && cc <= 122 /* z */) || (cc >= 48 /* 0 */ && cc <= 57 /* 9 */)) {
                    result += c;
                    prevdash = false;
                }
                else if ((cc >= 65 && cc <= 90 /* A - Z */)) {
                    result += c.toLowerCase();
                    prevdash = false;
                }
                else if (c == ' ' || c == ',' || c == '.' || c == '/' || c == '\\' || c == '-' || c == '_' || c == '=') {
                    if (!prevdash && result.length > 0) {
                        result += '-';
                        prevdash = true;
                    }
                }
                else if (cc >= 128) {
                    let prevlen = result.length;
                    result += remapInternationalCharToAscii(c);
                    if (prevlen != result.length) prevdash = false;
                }
                if (i == maxlen) break;
            }

            if (prevdash)
                return result.substring(0, result.length - 1);
            else
                return result;
        }