在进行url编码时，std :: regex_replace无法正确处理字符&"+&"字符. [英] While doing url encoding, the std::regex_replace doesn't work properly for character "+"
本文介绍了在进行url编码时，std :: regex_replace无法正确处理字符&"+&"字符.的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
下面是代码段，regex_replace不适用于字符"+"，我不应对字符进行特殊处理，但应能正常工作.
/*所有头文件均可用.*/std :: string charToHex(unsigned char c，bool bUpperCase);std :: string urlEncode(const std :: string& toEncode，bool bEncodeForwardSlash);std :: string getEncodedUrl(const std :: string& url){std :: string bktObjKey =";std :: string urlEnc = url;boost :: regex expression("^(([[^:/?#] +):)?(//([^/?#:] *)(:\\ d +)?)?([^?#]*)((\\?[^#] *))?(#(.*))?);std :: string :: const_iterator start = url.begin()，end = url.end();boost :: match_results< std :: string :: const_iterator>什么;boost :: match_flag_type标志= boost :: match_default;如果(regex_search(url.begin()，url.end()，什么，表达式，标志)){std :: cout<匹配的"<< std :: endl;bktObjKey.insert(bktObjKey.begin()，what [6] .first，what [6] .second);std :: regex fobj(bktObjKey);/* std :: string fobj = bktObjKey; *//*自动pos = url.find(bktObjKey); */bktObjKey = urlEncode(bktObjKey，false);std :: cout<"bktObjKey:"< bktObjKey.c_str()<"urlEnc:"<< urlEnc.c_str()<< std :: endl;urlEnc = std :: regex_replace(url，fobj，bktObjKey);std :: cout<<"urlEnc:"<< urlEnc.c_str()<< std :: endl;}返回urlEnc;}std :: string urlEncode(const std :: string& toEncode，bool bEncodeForwardSlash){std :: ostringstream out;std :: cout<<内部编码"<< std :: endl;for(std :: string :: size_type i = 0; i< toEncode.length(); ++ i){char ch = toEncode.at(i);如果((ch> ='A'& ch< ='Z')||(ch> ='a'& ch< ='z')||(ch> ='0'&&ch;< ='9')||(ch =='_'|| ch =='-'|| ch =='〜'|| ch =='.')||(ch =='/'&&！bEncodeForwardSlash)){出<<ch;std :: cout<< out.str()<<未编码为十六进制"<< std :: endl;}别的 {出<<％"<<charToHex(ch，true);std :: cout<< out.str()<<编码为十六进制"<< std :: endl;}}std :: cout<<返回:"<< out.str()<< std :: endl;返回out.str();}std :: string charToHex(unsigned char c，bool bUpperCase){简而言之，我= C;std :: stringstream s;s<<std :: setw(2)<<std :: setfill('0')<<std :: hex<<一世;返回s.str();}int main(){std :: string url1 ="http://10.130.0.36/rbkt10/+";std :: string out1 = getEncodedUrl(url1);std :: cout<<已编码的URL1 =:"<< out1<< std :: endl;返回0;} 输出:编码的URL1 =:
#include< boost/regex.hpp>#include< iostream>#include< iomanip>void writeHex(std :: ostream& os，无符号字符c，布尔型大写){os<<std :: setfill('0')<<std :: hex;如果(大写)os<<std ::大写;os<<'％'<<std :: setw(2)<<static_cast< int>(c);}void urlEncode(std :: ostream& os，const std :: string& toEncode，bool bEncodeForwardSlash){自动is_safe = [=](uint8_t ch){返回std :: isalnum(ch)||(ch =='/'&&！bEncodeForwardSlash)||std :: strchr("_-〜."，ch);};for(char ch:toEncode){如果(is_safe(ch))os<<ch;别的writeHex(os，ch，true);}}std :: string urlEncode(const std :: string& toEncode，bool bEncodeForwardSlash){std :: ostringstream out;urlEncode(out，toEncode，bEncodeForwardSlash);返回out.str();}std :: string getEncodedUrl(std :: string url){boost :: regex uri_regex(R(^((?? scheme> [^:/?#] +):)?)"R(((?< authority>//(\?< host> [^/?#:] *)(:(?(< port> \ d +))?)?)"R((?? path> [^?#] *))"R((\?(?< query>([^#] *))?)"R"(((#(α< fragment>.*))?)"))；boost :: match_results< std :: string :: iterator>什么;//boost :: smatch what;如果(regex_search(url.begin()，url.end()，什么，uri_regex)){自动&满=什么[0];自动&查询= what [查询"];自动&片段= what [片段"];std :: ostringstream out;出<<what ["scheme"]<<what ["authority"];urlEncode(out，what ["path"]，false);如果(query.matched)urlEncode(out<<'?'，query，true);如果(片段匹配)urlEncode(out<<'#'，片段，true);url.replace(full.begin()，full.end()，out.str());}返回网址；}int main(){对于(std :: string url:{"http://10.130.0.36/rbkt10/+"，"//10.130.0.36/rbkt10/+"，"//localhost:443/rbkt10/+"，"https:/rbkt10/+"，"https:/rbkt10/+?in_params ='请不要转义/(正斜杠)'& more#also = in/fragment"，文本http://10.130.0.36/rbkt10/+内的匹配有点模糊"，}){std :: cout<<编码的URL:"<<getEncodedUrl(url)<<std :: endl;}} 打印
编码的URL:http//10.130.0.36/rbkt10/％2B编码的网址://10.130.0.36/rbkt10/%2B编码的URL://localhost％3A443/rbkt10/％2B编码网址:https/rbkt10/％2B编码的URL:https/rbkt10/％2B?in_params％3D％27please％20do％20escape％20％2F％20％28forward％20slash％29％27％26more#also％3Din％2Ffragment编码的URL:匹配文本http//10.130.0.36/rbkt10/％2B％20is％20a％20bit％20fuzzy 注意
请注意，代码STILL不符合规范:
这就是为什么您使用库的原因.
¹(这会导致+从输入中保留.它不是重复的"，只是因为/+ 表示1个或多个/而不被替换).
²请参见 https://en.wikipedia.org/wiki/Uniform_Resource_Identifier#Generic_syntax
Following is the code snippet, the regex_replace dosn't work properly for character "+", I should not use special handling for the characters, but it should work properly.
/*All headerfiles are available.*/
std::string charToHex(unsigned char c, bool bUpperCase);
std::string urlEncode(const std::string& toEncode, bool bEncodeForwardSlash);
std::string getEncodedUrl(const std::string& url){
std::string bktObjKey = "";
std::string urlEnc = url;
boost::regex expression("^(([^:/?#]+):)?(//([^/?#:]*)(:\\d+)?)?([^?#]*)((\\?[^#]*))?(#(.*))?");
std::string::const_iterator start=url.begin(), end = url.end();
boost::match_results<std::string::const_iterator> what;
boost::match_flag_type flags = boost::match_default;
if (regex_search(url.begin(), url.end(), what, expression, flags)) {
std::cout<<"Matched"<<std::endl;
bktObjKey.insert(bktObjKey.begin(), what[6].first, what[6].second);
std::regex fobj(bktObjKey);
/*std::string fobj = bktObjKey;*/
/*auto pos = url.find(bktObjKey);*/
bktObjKey = urlEncode(bktObjKey, false);
std::cout<<"bktObjKey :"<<bktObjKey.c_str()<<" urlEnc: "<<urlEnc.c_str()<<std::endl;
urlEnc = std::regex_replace(url, fobj, bktObjKey);
std::cout<<" urlEnc: "<<urlEnc.c_str()<<std::endl;
}
return urlEnc;
}
std::string urlEncode(const std::string& toEncode, bool bEncodeForwardSlash) {
std::ostringstream out;
std::cout<<"inside encode"<<std::endl;
for(std::string::size_type i=0; i < toEncode.length(); ++i) {
char ch = toEncode.at(i);
if ((ch >= 'A' && ch <= 'Z') ||
(ch >= 'a' && ch <= 'z') ||
(ch >= '0' && ch <= '9') ||
(ch == '_' || ch == '-' || ch == '~' || ch == '.') ||
(ch == '/' && !bEncodeForwardSlash)) {
out << ch;
std::cout<<out.str()<<" Is not coded to HEX"<<std::endl;
}
else {
out << "%" << charToHex(ch, true);
std::cout<<out.str()<<" Is coded to HEX"<<std::endl;
}
}
std::cout<<"Return :"<<out.str()<<std::endl;
return out.str();
}
std::string charToHex(unsigned char c, bool bUpperCase) {
short i = c;
std::stringstream s;
s << std::setw(2) << std::setfill('0') << std::hex << i;
return s.str();
}
int main() {
std::string url1 ="http://10.130.0.36/rbkt10/+";
std::string out1 = getEncodedUrl(url1);
std::cout<<"Encoded URL1=:"<<out1<<std::endl;
return 0;
}
OUTPUT: Encoded URL1=:http://10.130.0.36/rbkt10/%2b+
So the out put becomes "++". It should be only "+". How can I make it work perfectly?
解决方案
You're interpreting the original string as a regex.
+is special in regex¹.You should simply use
std::string::replacebecause you don't need regex replace functionality:boost::smatch what; if (regex_search(url.cbegin(), url.cend(), what, expression)) { boost::ssub_match query = what[6]; url.replace(query.first, query.second, urlEncode(query.str(), false)); }Complicated, scattered code like this:
could simply be:std::string bktObjKey = what[6].str();Complicated loop
for (std::string::size_type i = 0; i < toEncode.length(); ++i) { char ch = toEncode.at(i);Could just be
for (char ch : toEncode) {charToHexcreates a new 2-char string everytime, using another stringstream everytime, copying the result out of the stringstream etc. Instead, just write to the stringstream you have and avoid all the inefficiency:void writeHex(std::ostream& os, unsigned char c, bool uppercase) { os << std::setfill('0') << std::hex; if (uppercase) os << std::uppercase; os << std::setw(2) << static_cast<int>(c); }Note this also fixes the fact that you forgot to use
bUppercaseLook at
<cctype>for help classifying characters.Use raw literals to write
boost::regex expression("^(([^:/?#]+):)?(//([^/?#:]*)(:\\d+)?)?([^?#]*)((\\?[^#]*))?(#(.*))?");instead as:
boost::regex expression(R"(^(([^:/?#]+):)?(//([^/?#:]*)(:\d+)?)?([^?#]*)((\?[^#]*))?(#(.*))?)");(no need to doubly escape
\dand\?)Either drop all the redundant sub-groups
boost::regex expression(R"(^([^:/?#]+:)?(//[^/?#:]*(:\d+)?)?[^?#]*(\?[^#]*)?(#.*)?)");OR make them maintainable and useful²:
boost::regex uri_regex( R"(^((?<scheme>[^:/?#]+):)?)" R"((?<authority>//(\?<host>[^/?#:]*)(:(?<port>\d+))?)?)" R"((?<path>[^?#]*))" R"((\?(?<query>([^#]*)))?)" R"((#(?<fragment>.*))?)");Now that you have access to logical components of the URI, apply it to know better when and where to encode:
std::string escaped = what["scheme"].str() + what["authority"].str() + urlEncode(what["path"].str(), false); if (query.matched) { escaped += '?'; escaped.append(urlEncode(query, true)); } if (fragment.matched) { escaped += '#'; escaped.append(urlEncode(fragment, true)); }Make an overload of
urlEncodethat takes an existing ostream reference instead of always creating your own:std::ostringstream out; out << what["scheme"] << what["authority"]; urlEncode(out, what["path"], false); if (query.matched) urlEncode(out << '?', query, true); if (fragment.matched) urlEncode(out << '#', fragment, true);
Code After Review
#include <boost/regex.hpp>
#include <iostream>
#include <iomanip>
void writeHex(std::ostream& os, unsigned char c, bool uppercase) {
os << std::setfill('0') << std::hex;
if (uppercase)
os << std::uppercase;
os << '%' << std::setw(2) << static_cast<int>(c);
}
void urlEncode(std::ostream& os, const std::string &toEncode, bool bEncodeForwardSlash) {
auto is_safe = [=](uint8_t ch) {
return std::isalnum(ch) ||
(ch == '/' && !bEncodeForwardSlash) ||
std::strchr("_-~.", ch);
};
for (char ch : toEncode) {
if (is_safe(ch))
os << ch;
else
writeHex(os, ch, true);
}
}
std::string urlEncode(const std::string &toEncode, bool bEncodeForwardSlash) {
std::ostringstream out;
urlEncode(out, toEncode, bEncodeForwardSlash);
return out.str();
}
std::string getEncodedUrl(std::string url) {
boost::regex uri_regex(
R"(^((?<scheme>[^:/?#]+):)?)"
R"((?<authority>//(\?<host>[^/?#:]*)(:(?<port>\d+))?)?)"
R"((?<path>[^?#]*))"
R"((\?(?<query>([^#]*)))?)"
R"((#(?<fragment>.*))?)");
boost::match_results<std::string::iterator> what;
//boost::smatch what;
if (regex_search(url.begin(), url.end(), what, uri_regex)) {
auto& full = what[0];
auto& query = what["query"];
auto& fragment = what["fragment"];
std::ostringstream out;
out << what["scheme"] << what["authority"];
urlEncode(out, what["path"], false);
if (query.matched)
urlEncode(out << '?', query, true);
if (fragment.matched)
urlEncode(out << '#', fragment, true);
url.replace(full.begin(), full.end(), out.str());
}
return url;
}
int main() {
for (std::string url : {
"http://10.130.0.36/rbkt10/+",
"//10.130.0.36/rbkt10/+",
"//localhost:443/rbkt10/+",
"https:/rbkt10/+",
"https:/rbkt10/+?in_params='please do escape / (forward slash)'&more#also=in/fragment",
"match inside text http://10.130.0.36/rbkt10/+ is a bit fuzzy",
}) {
std::cout << "Encoded URL: " << getEncodedUrl(url) << std::endl;
}
}
Prints
Encoded URL: http//10.130.0.36/rbkt10/%2B
Encoded URL: //10.130.0.36/rbkt10/%2B
Encoded URL: //localhost%3A443/rbkt10/%2B
Encoded URL: https/rbkt10/%2B
Encoded URL: https/rbkt10/%2B?in_params%3D%27please%20do%20escape%20%2F%20%28forward%20slash%29%27%26more#also%3Din%2Ffragment
Encoded URL: match inside text http//10.130.0.36/rbkt10/%2B%20is%20a%20bit%20fuzzy
CAUTION
Notice that the code STILL doesn't adhere to the specs:
This is why you use a library instead.
¹ (This causes + to be left from the input. It's not "repeated", it's just not replaced because /+ means 1 or more /).
² See https://en.wikipedia.org/wiki/Uniform_Resource_Identifier#Generic_syntax
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