如何检查给定的字符串是否是有效的URL地址?

我对正则表达式的知识是基本的,不允许我从我已经在网上看到的数百个正则表达式中进行选择。


当前回答

最佳正则表达式是这里最佳答案的组合!哈哈哈!我刚刚测试了它们,并把最好的放在一起!我稍微改变了一下,只有一个捕获组!我在这个页面的源代码中找到了637个url !只有几个假阳性!

((?:(?:https?|ftp)://)(?:\S+(?::\S*)?@|\d{1,3}(?:\.\d{1,3}){3}|(?:(?:[a-z\d\x{00a1}-\x{ffff}]+-?)*[a-z\d\x{00a1}-\x{ffff}]+)(?:\.(?:[a-z\d\x{00a1}-\x{ffff}]+-?)*[a-z\d\x{00a1}-\x{ffff}]+)*(?:\.[a-z\x{00a1}-\x{ffff}]{2,6}))(?::\d+)?(?:[^\s]*)|(?:(?:(?:[A-Za-z]{3,9}:(?:\/\/)?)(?:[-;:&=\+\$,\w]+@)?[A-Za-z0-9.-]+(?::[0-9]+)?|(?:www.|[-;:&=\+\$,\w]+@)[A-Za-z0-9.-]+)(?:(?:\/[\+~%\/.\w-_]*)?\??(?:[-\+=&;%@.\w_]*)#?(?:[\w]*))?)|(?:(?:(?:(?:[A-Za-z]{3,9}:(?:\/\/)?)(?:[-;:&=\+\$,\w]+@)?[A-Za-z0-9.-]+|(?:www.|[-;:&=\+\$,\w]+@)[A-Za-z0-9.-]+)(?:(?:\/[\+~%\/.\w-_]*)?\??(?:[-\+=&;%@.\w_]*)#?(?:[\w]*))?))|(?:(?:(?:[\\w]+:)?//)?(?:(?:[\\d\\w]|%[a-fA-f\\d]{2,2})+(?::(?:[\\d\\w]|%[a-fA-f\\d]{2,2})+)?@)?(?:[\\d\\w][-\\d\\w]{0,253}[\\d\\w]\\.)+[\\w]{2,4}(?::[\\d]+)?(?:/(?:[-+_~.\\d\\w]|%[a-fA-f\\d]{2,2})*)*(?:\\?(?:&?(?:[-+_~.\\d\\w]|%[a-fA-f\\d]{2,2})=?)*)?(?:#(?:[-+_~.\\d\\w]|%[a-fA-f\\d]{2,2})*)?)|(?:https?:\/\/(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z0-9][a-z0-9-]{0,61}[a-z0-9])(?::?\d*)\/?(?:[a-z_\/0-9\-#.]*)\??(?:[a-z_\/0-9\-#=&]*)|(?:(?:(?:https?:)?(?:\/?\/))(?:(?:[\d\w]|%[a-fA-f\d]{2,2})+(?::(?:[\d\w]|%[a-fA-f\d]{2,2})+)?@)?(?:[\d\w][-\d\w]{0,253}[\d\w]\.)+[\w]{2,63}(?::[\d]+)?(?:/(?:[-+_~.\d\w]|%[a-fA-f\d]{2,2})*)*(?:\?(?:&?(?:[-+_~.\d\w]|%[a-fA-f\d]{2,2})=?)*)?(?:#(?:[-+_~.\d\w]|%[a-fA-f\d]{2,2})*)?)|(?:(?:https?|ftp)://(?:www\d?|[a-zA-Z0-9]+)?\.[a-zA-Z0-9-]+(?:\:|\.)(?:[a-zA-Z0-9.]+|(?:\d+)?)(?:[/?:].*)?)|(?:\b(?:(?:https?|ftp):\/\/)(?:\S+(?::\S*)?@)?(?:(?!10(?:\.\d{1,3}){3})(?!127(?:\.\d{1,3}){3})(?!169\.254(?:\.\d{1,3}){2})(?!192\.168(?:\.\d{1,3}){2})(?!172\.(?:1[6-9]|2\d|3[0-1])(?:\.\d{1,3}){2})(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))|(?:(?:[a-z\x{00a1}-\x{ffff}0-9]+-?)*[a-z\x{00a1}-\x{ffff}0-9]+)(?:\.(?:[a-z\x{00a1}-\x{ffff}0-9]+-?)*[a-z\x{00a1}-\x{ffff}0-9]+)*(?:\.(?:[a-z\x{00a1}-\x{ffff}]{2,})))(?::\d{2,5})?(?:\/[^\s]*)?\b))

其他回答

我写了一个很棒的版本,你可以运行

它匹配以下url(这对我来说已经足够好了)

public static void main(args) {
    String url = "go to http://www.m.abut.ly/abc its awesome"
    url = url.replaceAll(/https?:\/\/w{0,3}\w*?\.(\w*?\.)?\w{2,3}\S*|www\.(\w*?\.)?\w*?\.\w{2,3}\S*|(\w*?\.)?\w*?\.\w{2,3}[\/\?]\S*/ , { it ->
        "woof${it}woof"
    })
    println url 
}
http://google.com
http://google.com/help.php
http://google.com/help.php?a=5

http://www.google.com
http://www.google.com/help.php
http://www.google.com?a=5

google.com?a=5
google.com/help.php
google.com/help.php?a=5

http://www.m.google.com/help.php?a=5 (and all its permutations)
www.m.google.com/help.php?a=5 (and all its permutations)
m.google.com/help.php?a=5 (and all its permutations)

对于任何不以http或www开头的url,重要的是它们必须包含/或?

我打赌这可以稍作调整,但它的工作非常好,因为它是如此简短和紧凑……因为你可以把它分成三份:

找到任何以http开头的内容:

https?:\/\/w{0,3}\w*?\.\w{2,3}\S*

找到任何以www开头的东西:

www\.\w*?\.\w{2,3}\S*

或者找到任何必须有一个文本,然后一个点,然后至少两个字母,然后一个?或/:

\w*?\.\w{2,3}[\/\?]\S*

我想我找到了一个更通用的regexp来验证url,特别是网站

​(https?:\/\/)?(www\.)[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,4}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)|(https?:\/\/)?(www\.)?(?!ww)[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,4}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)

它不允许例如www.something或http://www或http://www.something

点击这里查看:http://regexr.com/3e4a2

这个怎么样:

^(https?:\/\/(?:www\.|(?!www))[a-zA-Z0-9][a-zA-Z0-9-]+[a-zA-Z0-9]\.[^\s]{2,}|www\.[a-zA-Z0-9][a-zA-Z0-9-]+[a-zA-Z0-9]\.[^\s]{2,}|https?:\/\/(?:www\.|(?!www))[a-zA-Z0-9]\.[^\s]{2,}|www\.[a-zA-Z0-9]\.[^\s]{2,})$

这些是测试用例:

你可以在这里试试:https://regex101.com/r/mS9gD7/41

如果你想采用更严格的规则,以下是我提出的:

isValidUrl(input) {
    var regex = /^(((H|h)(T|t)(T|t)(P|p)(S|s)?):\/\/)?[-a-zA-Z0-9@:%._\+~#=]{2,100}\.[a-zA-Z]{2,10}(\/([-a-zA-Z0-9@:%_\+.~#?&//=]*))?/
    return regex.test(input)
}

感谢@eyelidlessness提供了非常彻底(尽管很长)的基于RFC的正则表达式。

然而,对于那些使用EICMAScript / JavaScript / Apps Script的人来说,它不起作用。以下是他的答案的精确副本,可以与这些问题一起工作(以及一个代码片段,例如-整洁的新功能!):

regEx_valid_URL = /^[a-z](?:[-a-z0-9\+\.])*:(?:\/\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=:])*@)?(?:\[(?:(?:(?:[0-9a-f]{1,4}:){6}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|::(?:[0-9a-f]{1,4}:){5}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:[0-9a-f]{1,4})?::(?:[0-9a-f]{1,4}:){4}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:(?:[0-9a-f]{1,4}:){0,1}[0-9a-f]{1,4})?::(?:[0-9a-f]{1,4}:){3}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:(?:[0-9a-f]{1,4}:){0,2}[0-9a-f]{1,4})?::(?:[0-9a-f]{1,4}:){2}(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:(?:[0-9a-f]{1,4}:){0,3}[0-9a-f]{1,4})?::[0-9a-f]{1,4}:(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:(?:[0-9a-f]{1,4}:){0,4}[0-9a-f]{1,4})?::(?:[0-9a-f]{1,4}:[0-9a-f]{1,4}|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3})|(?:(?:[0-9a-f]{1,4}:){0,5}[0-9a-f]{1,4})?::[0-9a-f]{1,4}|(?:(?:[0-9a-f]{1,4}:){0,6}[0-9a-f]{1,4})?::)|v[0-9a-f]+\.[-a-z0-9\._~!\$&'\(\)\*\+,;=:]+)\]|(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])(?:\.(?:[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])){3}|(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0}-\uD7FF}\uF900-\uFDCF}\uFDF0}-\uFFEF}\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=])*)(?::[0-9]*)?(?:\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0}-\uD7FF}\uF900-\uFDCF}\uFDF0}-\uFFEF}\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=:@]))*)*|\/(?:(?:(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0}-\uD7FF}\uF900-\uFDCF}\uFDF0}-\uFFEF}\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=:@]))+)(?:\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0}-\uD7FF}\uF900-\uFDCF}\uFDF0}-\uFFEF}\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=:@]))*)*)?|(?:(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0}-\uD7FF}\uF900-\uFDCF}\uFDF0}-\uFFEF}\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=:@]))+)(?:\/(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0}-\uD7FF}\uF900-\uFDCF}\uFDF0}-\uFFEF}\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=:@]))*)*|(?!(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0}-\uD7FF}\uF900-\uFDCF}\uFDF0}-\uFFEF}\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=:@])))(?:\?(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0}-\uD7FF}\uF900-\uFDCF}\uFDF0}-\uFFEF}\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=:@])|[\uE000-\uF8FF}\uF0000-\uFFFFD\u100000-\u10FFFD\/\?])*)?(?:\#(?:(?:%[0-9a-f][0-9a-f]|[-a-z0-9\._~\uA0}-\uD7FF}\uF900-\uFDCF}\uFDF0}-\uFFEF}\u10000-\u1FFFD\u20000-\u2FFFD\u30000-\u3FFFD\u40000-\u4FFFD\u50000-\u5FFFD\u60000-\u6FFFD\u70000-\u7FFFD\u80000-\u8FFFD\u90000-\u9FFFD\uA0000-\uAFFFD\uB0000-\uBFFFD\uC0000-\uCFFFD\uD0000-\uDFFFD\uE1000-\uEFFFD!\$&'\(\)\*\+,;=:@])|[\/\?])*)?$/i; checkedURL = RegExp(regEx_valid_URL).exec('gopher://example.somewhere.university/'); if (checkedURL != null) { console.log('The URL ' + checkedURL + ' is valid'); }