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
黑(http / \ /处事之道会(s) ?):地球,随便(www。)? a-zA-Z0-9 @:%._\+~#=]{ 地球,随便2,256出于美观。黑a-z铝可不,2、6出于美观\ b(黑-a-zA-Z0-9 @:%_\+.~#?&//=]*)
其他回答
下面是Android源代码的Java版本。这是我找到的最好的一个。
public static final Matcher WEB = Pattern.compile(new StringBuilder()
.append("((?:(http|https|Http|Https|rtsp|Rtsp):")
.append("\\/\\/(?:(?:[a-zA-Z0-9\\$\\-\\_\\.\\+\\!\\*\\'\\(\\)")
.append("\\,\\;\\?\\&\\=]|(?:\\%[a-fA-F0-9]{2})){1,64}(?:\\:(?:[a-zA-Z0-9\\$\\-\\_")
.append("\\.\\+\\!\\*\\'\\(\\)\\,\\;\\?\\&\\=]|(?:\\%[a-fA-F0-9]{2})){1,25})?\\@)?)?")
.append("((?:(?:[a-zA-Z0-9][a-zA-Z0-9\\-]{0,64}\\.)+") // named host
.append("(?:") // plus top level domain
.append("(?:aero|arpa|asia|a[cdefgilmnoqrstuwxz])")
.append("|(?:biz|b[abdefghijmnorstvwyz])")
.append("|(?:cat|com|coop|c[acdfghiklmnoruvxyz])")
.append("|d[ejkmoz]")
.append("|(?:edu|e[cegrstu])")
.append("|f[ijkmor]")
.append("|(?:gov|g[abdefghilmnpqrstuwy])")
.append("|h[kmnrtu]")
.append("|(?:info|int|i[delmnoqrst])")
.append("|(?:jobs|j[emop])")
.append("|k[eghimnrwyz]")
.append("|l[abcikrstuvy]")
.append("|(?:mil|mobi|museum|m[acdghklmnopqrstuvwxyz])")
.append("|(?:name|net|n[acefgilopruz])")
.append("|(?:org|om)")
.append("|(?:pro|p[aefghklmnrstwy])")
.append("|qa")
.append("|r[eouw]")
.append("|s[abcdeghijklmnortuvyz]")
.append("|(?:tel|travel|t[cdfghjklmnoprtvwz])")
.append("|u[agkmsyz]")
.append("|v[aceginu]")
.append("|w[fs]")
.append("|y[etu]")
.append("|z[amw]))")
.append("|(?:(?:25[0-5]|2[0-4]") // or ip address
.append("[0-9]|[0-1][0-9]{2}|[1-9][0-9]|[1-9])\\.(?:25[0-5]|2[0-4][0-9]")
.append("|[0-1][0-9]{2}|[1-9][0-9]|[1-9]|0)\\.(?:25[0-5]|2[0-4][0-9]|[0-1]")
.append("[0-9]{2}|[1-9][0-9]|[1-9]|0)\\.(?:25[0-5]|2[0-4][0-9]|[0-1][0-9]{2}")
.append("|[1-9][0-9]|[0-9])))")
.append("(?:\\:\\d{1,5})?)") // plus option port number
.append("(\\/(?:(?:[a-zA-Z0-9\\;\\/\\?\\:\\@\\&\\=\\#\\~") // plus option query params
.append("\\-\\.\\+\\!\\*\\'\\(\\)\\,\\_])|(?:\\%[a-fA-F0-9]{2}))*)?")
.append("(?:\\b|$)").toString()
).matcher("");
关于眼睑问题，他的回答是“这是基于我对URI规范的阅读。”谢谢眼睑，你的是我寻求的完美的解决方案，因为它是基于URI规范!出色的工作。：）
我不得不做了两个修改。第一个在PHP (v5.2.10)中使用preg_match()函数使regexp正确匹配IP地址url的方法。
我不得不在管道周围的“IP Address”上方的行中添加一组括号:
)|((\d|[1-9]\d|1\d{2}|2[0-4][0-9]|25[0-5])\.){3}(?#
不知道为什么。
我还将顶级域名的最小长度从3个字母减少到2个字母，以支持.co。英国和类似国家。
最后的代码:
/^(https?|ftp):\/\/(?# protocol
)(([a-z0-9$_\.\+!\*\'\(\),;\?&=-]|%[0-9a-f]{2})+(?# username
)(:([a-z0-9$_\.\+!\*\'\(\),;\?&=-]|%[0-9a-f]{2})+)?(?# password
)@)?(?# auth requires @
)((([a-z0-9]\.|[a-z0-9][a-z0-9-]*[a-z0-9]\.)*(?# domain segments AND
)[a-z][a-z0-9-]*[a-z0-9](?# top level domain OR
)|((\d|[1-9]\d|1\d{2}|2[0-4][0-9]|25[0-5])\.){3}(?#
)(\d|[1-9]\d|1\d{2}|2[0-4][0-9]|25[0-5])(?# IP address
))(:\d+)?(?# port
))(((\/+([a-z0-9$_\.\+!\*\'\(\),;:@&=-]|%[0-9a-f]{2})*)*(?# path
)(\?([a-z0-9$_\.\+!\*\'\(\),;:@&=-]|%[0-9a-f]{2})*)(?# query string
)?)?)?(?# path and query string optional
)(#([a-z0-9$_\.\+!\*\'\(\),;:@&=-]|%[0-9a-f]{2})*)?(?# fragment
)$/i
这个修改后的版本没有根据URI规范进行检查，所以我不能保证它的合规性，它被修改为处理本地网络环境中的URL和两位tld以及其他类型的Web URL，并在我使用的PHP设置中更好地工作。
作为PHP代码:
define('URL_FORMAT',
'/^(https?):\/\/'. // protocol
'(([a-z0-9$_\.\+!\*\'\(\),;\?&=-]|%[0-9a-f]{2})+'. // username
'(:([a-z0-9$_\.\+!\*\'\(\),;\?&=-]|%[0-9a-f]{2})+)?'. // password
'@)?(?#'. // auth requires @
')((([a-z0-9]\.|[a-z0-9][a-z0-9-]*[a-z0-9]\.)*'. // domain segments AND
'[a-z][a-z0-9-]*[a-z0-9]'. // top level domain OR
'|((\d|[1-9]\d|1\d{2}|2[0-4][0-9]|25[0-5])\.){3}'.
'(\d|[1-9]\d|1\d{2}|2[0-4][0-9]|25[0-5])'. // IP address
')(:\d+)?'. // port
')(((\/+([a-z0-9$_\.\+!\*\'\(\),;:@&=-]|%[0-9a-f]{2})*)*'. // path
'(\?([a-z0-9$_\.\+!\*\'\(\),;:@&=-]|%[0-9a-f]{2})*)'. // query string
'?)?)?'. // path and query string optional
'(#([a-z0-9$_\.\+!\*\'\(\),;:@&=-]|%[0-9a-f]{2})*)?'. // fragment
'$/i');
下面是一个PHP测试程序，它使用正则表达式验证各种url:
<?php
define('URL_FORMAT',
'/^(https?):\/\/'. // protocol
'(([a-z0-9$_\.\+!\*\'\(\),;\?&=-]|%[0-9a-f]{2})+'. // username
'(:([a-z0-9$_\.\+!\*\'\(\),;\?&=-]|%[0-9a-f]{2})+)?'. // password
'@)?(?#'. // auth requires @
')((([a-z0-9]\.|[a-z0-9][a-z0-9-]*[a-z0-9]\.)*'. // domain segments AND
'[a-z][a-z0-9-]*[a-z0-9]'. // top level domain OR
'|((\d|[1-9]\d|1\d{2}|2[0-4][0-9]|25[0-5])\.){3}'.
'(\d|[1-9]\d|1\d{2}|2[0-4][0-9]|25[0-5])'. // IP address
')(:\d+)?'. // port
')(((\/+([a-z0-9$_\.\+!\*\'\(\),;:@&=-]|%[0-9a-f]{2})*)*'. // path
'(\?([a-z0-9$_\.\+!\*\'\(\),;:@&=-]|%[0-9a-f]{2})*)'. // query string
'?)?)?'. // path and query string optional
'(#([a-z0-9$_\.\+!\*\'\(\),;:@&=-]|%[0-9a-f]{2})*)?'. // fragment
'$/i');
/**
* Verify the syntax of the given URL.
*
* @access public
* @param $url The URL to verify.
* @return boolean
*/
function is_valid_url($url) {
if (str_starts_with(strtolower($url), 'http://localhost')) {
return true;
}
return preg_match(URL_FORMAT, $url);
}
/**
* String starts with something
*
* This function will return true only if input string starts with
* niddle
*
* @param string $string Input string
* @param string $niddle Needle string
* @return boolean
*/
function str_starts_with($string, $niddle) {
return substr($string, 0, strlen($niddle)) == $niddle;
}
/**
* Test a URL for validity and count results.
* @param url url
* @param expected expected result (true or false)
*/
$numtests = 0;
$passed = 0;
function test_url($url, $expected) {
global $numtests, $passed;
$numtests++;
$valid = is_valid_url($url);
echo "URL Valid?: " . ($valid?"yes":"no") . " for URL: $url. Expected: ".($expected?"yes":"no").". ";
if($valid == $expected) {
echo "PASS\n"; $passed++;
} else {
echo "FAIL\n";
}
}
echo "URL Tests:\n\n";
test_url("http://localserver/projects/public/assets/javascript/widgets/UserBoxMenu/widget.css", true);
test_url("http://www.google.com", true);
test_url("http://www.google.co.uk/projects/my%20folder/test.php", true);
test_url("https://myserver.localdomain", true);
test_url("http://192.168.1.120/projects/index.php", true);
test_url("http://192.168.1.1/projects/index.php", true);
test_url("http://projectpier-server.localdomain/projects/public/assets/javascript/widgets/UserBoxMenu/widget.css", true);
test_url("https://2.4.168.19/project-pier?c=test&a=b", true);
test_url("https://localhost/a/b/c/test.php?c=controller&arg1=20&arg2=20", true);
test_url("http://user:password@localhost/a/b/c/test.php?c=controller&arg1=20&arg2=20", true);
echo "\n$passed out of $numtests tests passed.\n\n";
?>
再次感谢regex的虚实!
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'); }
https?:\/{2}(?:[\/-\w.]|(?:%[\da-fA-F]{2}))+
您可以使用此模式来检测url。
下面是概念的证明
RegExr: URL检测器
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)
}
