html的轉義字符然后通過代碼識別

這篇文章主要講解了“html的轉義字符然后通過代碼識別”，文中的講解內容簡單清晰，易于學習與理解，下面請大家跟著小編的思路慢慢深入，一起來研究和學習“html的轉義字符然后通過代碼識別”吧！

　　偶爾會在數據中看到諸如'這樣的字符，特征如下

　　以&#開頭，中間是一串數字，以；結尾

　　以&開頭，中間一串字符，以；結尾

　　比如最常見的 或者等價的 

　　瀏覽器遇到這些轉義符，會轉義回來，但如何通過代碼識別？org.apache.commons.lang.StringEscapeUtils.unescapeHtml提供了很好的說明

　　遇到上面的第一種情況，中間是數字的，直接將數字（unicode）轉為char

　　遇到第二情況，中間是字符，只能查映射表了,從映射表中找到字符對應的數字再轉換為char看看代碼就一目了然了

　　看看HTML40如何定義的

　　static{

　　HTML40=newEntities();

　　fillWithHtml40Entities(HTML40);

　　}

　　staticvoidfillWithHtml40Entities(Entitiesentities){

　　entities.addEntities(BASIC_ARRAY);

　　entities.addEntities(ISO8859_1_ARRAY);

　　entities.addEntities(HTML40_ARRAY);

　　}

　　再看看BASIC_ARRAY、ISO8859_1_ARRAY、HTML40_ARRAY分別是什么

　　BASIC_ARRAY

　　privatestaticfinalString[][]BASIC_ARRAY={{"quot","34"},//"-double-quote

　　{"amp","38"},//&-ampersand

　　{"lt","60"},//<-less-than

　　{"gt","62"},//>-greater-than

　　};

　　ISO8859_1_ARRAY

　　staticfinalString[][]ISO8859_1_ARRAY={{"nbsp","160"},//non-breakingspace

　　{"iexcl","161"},//invertedexclamationmark

　　{"cent","162"},//centsign

　　{"pound","163"},//poundsign

　　{"curren","164"},//currencysign

　　{"yen","165"},//yensign=yuansign

　　{"brvbar","166"},//brokenbar=brokenverticalbar

　　{"sect","167"},//sectionsign

　　{"uml","168"},//diaeresis=spacingdiaeresis

　　{"copy","169"},//?-copyrightsign

　　{"ordf","170"},//feminineordinalindicator

　　{"laquo","171"},//left-pointingdoubleanglequotationmark=leftpointingguillemet

　　{"not","172"},//notsign

　　{"shy","173"},//softhyphen=discretionaryhyphen

　　{"reg","174"},//?-registeredtrademarksign

　　{"macr","175"},//macron=spacingmacron=overline=APLoverbar

　　{"deg","176"},//degreesign

　　{"plusmn","177"},//plus-minussign=plus-or-minussign

　　{"sup2","178"},//superscripttwo=superscriptdigittwo=squared

　　{"sup3","179"},//superscriptthree=superscriptdigitthree=cubed

　　{"acute","180"},//acuteaccent=spacingacute

　　{"micro","181"},//microsign

　　{"para","182"},//pilcrowsign=paragraphsign

　　{"middot","183"},//middledot=Georgiancomma=Greekmiddledot

　　{"cedil","184"},//cedilla=spacingcedilla

　　{"sup1","185"},//superscriptone=superscriptdigitone

　　{"ordm","186"},//masculineordinalindicator

　　{"raquo","187"},//right-pointingdoubleanglequotationmark=rightpointingguillemet

　　{"frac14","188"},//vulgarfractiononequarter=fractiononequarter

　　{"frac12","189"},//vulgarfractiononehalf=fractiononehalf

　　{"frac34","190"},//vulgarfractionthreequarters=fractionthreequarters

　　{"iquest","191"},//invertedquestionmark=turnedquestionmark

　　{"Agrave","192"},//?-uppercaseA,graveaccent

　　{"Aacute","193"},//?-uppercaseA,acuteaccent

　　{"Acirc","194"},//?-uppercaseA,circumflexaccent

　　{"Atilde","195"},//?-uppercaseA,tilde

　　{"Auml","196"},//?-uppercaseA,umlaut

　　{"Aring","197"},//?-uppercaseA,ring

　　{"AElig","198"},//?-uppercaseAE

　　{"Ccedil","199"},//?-uppercaseC,cedilla

　　{"Egrave","200"},//?-uppercaseE,graveaccent

　　{"Eacute","201"},//?-uppercaseE,acuteaccent

　　{"Ecirc","202"},//?-uppercaseE,circumflexaccent

　　{"Euml","203"},//?-uppercaseE,umlaut

　　{"Igrave","204"},//?-uppercaseI,graveaccent

　　{"Iacute","205"},//?-uppercaseI,acuteaccent

　　{"Icirc","206"},//?-uppercaseI,circumflexaccent

　　{"Iuml","207"},//?-uppercaseI,umlaut

　　{"ETH","208"},//?-uppercaseEth,Icelandic

　　{"Ntilde","209"},//?-uppercaseN,tilde

　　{"Ograve","210"},//?-uppercaseO,graveaccent

　　{"Oacute","211"},//?-uppercaseO,acuteaccent

　　{"Ocirc","212"},//?-uppercaseO,circumflexaccent

　　{"Otilde","213"},//?-uppercaseO,tilde

　　{"Ouml","214"},//?-uppercaseO,umlaut

　　{"times","215"},//multiplicationsign

　　{"Oslash","216"},//?-uppercaseO,slash

　　{"Ugrave","217"},//?-uppercaseU,graveaccent

　　{"Uacute","218"},//?-uppercaseU,acuteaccent

　　{"Ucirc","219"},//?-uppercaseU,circumflexaccent

　　{"Uuml","220"},//?-uppercaseU,umlaut

　　{"Yacute","221"},//?-uppercaseY,acuteaccent

　　{"THORN","222"},//?-uppercaseTHORN,Icelandic

　　{"szlig","223"},//?-lowercasesharps,German

　　{"agrave","224"},//?-lowercasea,graveaccent

　　{"aacute","225"},//?-lowercasea,acuteaccent

　　{"acirc","226"},//?-lowercasea,circumflexaccent

　　{"atilde","227"},//?-lowercasea,tilde

　　{"auml","228"},//?-lowercasea,umlaut

　　{"aring","229"},//?-lowercasea,ring

　　{"aelig","230"},//?-lowercaseae

　　{"ccedil","231"},//?-lowercasec,cedilla

　　{"egrave","232"},//?-lowercasee,graveaccent

　　{"eacute","233"},//?-lowercasee,acuteaccent

　　{"ecirc","234"},//?-lowercasee,circumflexaccent

　　{"euml","235"},//?-lowercasee,umlaut

　　{"igrave","236"},//?-lowercasei,graveaccent

　　{"iacute","237"},//?-lowercasei,acuteaccent

　　{"icirc","238"},//?-lowercasei,circumflexaccent

　　{"iuml","239"},//?-lowercasei,umlaut

　　{"eth","240"},//?-lowercaseeth,Icelandic

　　{"ntilde","241"},//?-lowercasen,tilde

　　{"ograve","242"},//?-lowercaseo,graveaccent

　　{"oacute","243"},//?-lowercaseo,acuteaccent

　　{"ocirc","244"},//?-lowercaseo,circumflexaccent

　　{"otilde","245"},//?-lowercaseo,tilde

　　{"ouml","246"},//?-lowercaseo,umlaut

　　{"divide","247"},//divisionsign

　　{"oslash","248"},//?-lowercaseo,slash

　　{"ugrave","249"},//?-lowercaseu,graveaccent

　　{"uacute","250"},//?-lowercaseu,acuteaccent

　　{"ucirc","251"},//?-lowercaseu,circumflexaccent

　　{"uuml","252"},//?-lowercaseu,umlaut

　　{"yacute","253"},//?-lowercasey,acuteaccent

　　{"thorn","254"},//?-lowercasethorn,Icelandic

　　{"yuml","255"},//?-lowercasey,umlaut

　　};

　　HTML40_ARRAY

　　staticfinalString[][]HTML40_ARRAY={

　　//<!--LatinExtended-B-->

　　{"fnof","402"},//latinsmallfwithhook=function=florin,U+0192ISOtech-->

　　//<!--Greek-->

　　{"Alpha","913"},//greekcapitalletteralpha,U+0391-->

　　{"Beta","914"},//greekcapitalletterbeta,U+0392-->

　　{"Gamma","915"},//greekcapitallettergamma,U+0393ISOgrk3-->

　　{"Delta","916"},//greekcapitalletterdelta,U+0394ISOgrk3-->

　　{"Epsilon","917"},//greekcapitalletterepsilon,U+0395-->

　　{"Zeta","918"},//greekcapitalletterzeta,U+0396-->

　　{"Eta","919"},//greekcapitallettereta,U+0397-->

　　{"Theta","920"},//greekcapitallettertheta,U+0398ISOgrk3-->

　　{"Iota","921"},//greekcapitalletteriota,U+0399-->

　　{"Kappa","922"},//greekcapitalletterkappa,U+039A-->

　　{"Lambda","923"},//greekcapitalletterlambda,U+039BISOgrk3-->

　　{"Mu","924"},//greekcapitallettermu,U+039C-->

　　{"Nu","925"},//greekcapitalletternu,U+039D-->

　　{"Xi","926"},//greekcapitalletterxi,U+039EISOgrk3-->

　　{"Omicron","927"},//greekcapitalletteromicron,U+039F-->

　　{"Pi","928"},//greekcapitalletterpi,U+03A0ISOgrk3-->

　　{"Rho","929"},//greekcapitalletterrho,U+03A1-->

　　//<!--thereisnoSigmaf,andnoU+03A2charactereither-->

　　{"Sigma","931"},//greekcapitallettersigma,U+03A3ISOgrk3-->

　　{"Tau","932"},//greekcapitallettertau,U+03A4-->

　　{"Upsilon","933"},//greekcapitalletterupsilon,U+03A5ISOgrk3-->

　　{"Phi","934"},//greekcapitalletterphi,U+03A6ISOgrk3-->

　　{"Chi","935"},//greekcapitalletterchi,U+03A7-->

　　{"Psi","936"},//greekcapitalletterpsi,U+03A8ISOgrk3-->

　　{"Omega","937"},//greekcapitalletteromega,U+03A9ISOgrk3-->

　　{"alpha","945"},//greeksmallletteralpha,U+03B1ISOgrk3-->

　　{"beta","946"},//greeksmallletterbeta,U+03B2ISOgrk3-->

　　{"gamma","947"},//greeksmalllettergamma,U+03B3ISOgrk3-->

　　{"delta","948"},//greeksmallletterdelta,U+03B4ISOgrk3-->

　　{"epsilon","949"},//greeksmallletterepsilon,U+03B5ISOgrk3-->

　　{"zeta","950"},//greeksmallletterzeta,U+03B6ISOgrk3-->

　　{"eta","951"},//greeksmalllettereta,U+03B7ISOgrk3-->

　　{"theta","952"},//greeksmalllettertheta,U+03B8ISOgrk3-->

　　{"iota","953"},//greeksmallletteriota,U+03B9ISOgrk3-->

　　{"kappa","954"},//greeksmallletterkappa,U+03BAISOgrk3-->

　　{"lambda","955"},//greeksmallletterlambda,U+03BBISOgrk3-->

　　{"mu","956"},//greeksmalllettermu,U+03BCISOgrk3-->

　　{"nu","957"},//greeksmallletternu,U+03BDISOgrk3-->

　　{"xi","958"},//greeksmallletterxi,U+03BEISOgrk3-->

　　{"omicron","959"},//greeksmallletteromicron,U+03BFNEW-->

　　{"pi","960"},//greeksmallletterpi,U+03C0ISOgrk3-->

　　{"rho","961"},//greeksmallletterrho,U+03C1ISOgrk3-->

　　{"sigmaf","962"},//greeksmallletterfinalsigma,U+03C2ISOgrk3-->

　　{"sigma","963"},//greeksmalllettersigma,U+03C3ISOgrk3-->

　　{"tau","964"},//greeksmalllettertau,U+03C4ISOgrk3-->

　　{"upsilon","965"},//greeksmallletterupsilon,U+03C5ISOgrk3-->

　　{"phi","966"},//greeksmallletterphi,U+03C6ISOgrk3-->

　　{"chi","967"},//greeksmallletterchi,U+03C7ISOgrk3-->

　　{"psi","968"},//greeksmallletterpsi,U+03C8ISOgrk3-->

　　{"omega","969"},//greeksmallletteromega,U+03C9ISOgrk3-->

　　{"thetasym","977"},//greeksmallletterthetasymbol,U+03D1NEW-->

　　{"upsih","978"},//greekupsilonwithhooksymbol,U+03D2NEW-->

　　{"piv","982"},//greekpisymbol,U+03D6ISOgrk3-->

　　//<!--GeneralPunctuation-->

　　{"bull","8226"},//bullet=blacksmallcircle,U+2022ISOpub-->

　　//<!--bulletisNOTthesameasbulletoperator,U+2219-->

　　{"hellip","8230"},//horizontalellipsis=threedotleader,U+2026ISOpub-->

　　{"prime","8242"},//prime=minutes=feet,U+2032ISOtech-->

　　{"Prime","8243"},//doubleprime=seconds=inches,U+2033ISOtech-->

　　{"oline","8254"},//overline=spacingoverscore,U+203ENEW-->

　　{"frasl","8260"},//fractionslash,U+2044NEW-->

　　//<!--LetterlikeSymbols-->

　　{"weierp","8472"},//scriptcapitalP=powerset=Weierstrassp,U+2118ISOamso-->

　　{"image","8465"},//blacklettercapitalI=imaginarypart,U+2111ISOamso-->

　　{"real","8476"},//blacklettercapitalR=realpartsymbol,U+211CISOamso-->

　　{"trade","8482"},//trademarksign,U+2122ISOnum-->

　　{"alefsym","8501"},//alefsymbol=firsttransfinitecardinal,U+2135NEW-->

　　//<!--alefsymbolisNOTthesameashebrewletteralef,U+05D0althoughthe

　　//sameglyphcouldbeusedtodepictbothcharacters-->

　　//<!--Arrows-->

　　{"larr","8592"},//leftwardsarrow,U+2190ISOnum-->

　　{"uarr","8593"},//upwardsarrow,U+2191ISOnum-->

　　{"rarr","8594"},//rightwardsarrow,U+2192ISOnum-->

　　{"darr","8595"},//downwardsarrow,U+2193ISOnum-->

　　{"harr","8596"},//leftrightarrow,U+2194ISOamsa-->

　　{"crarr","8629"},//downwardsarrowwithcornerleftwards=carriagereturn,U+21B5NEW-->

　　{"lArr","8656"},//leftwardsdoublearrow,U+21D0ISOtech-->

　　//<!--ISO10646doesnotsaythatlArristhesameasthe'isimpliedby'

　　//arrowbutalsodoesnothaveanyothercharacterforthatfunction.

　　//So?lArrcanbeusedfor'isimpliedby'asISOtechsuggests-->

　　{"uArr","8657"},//upwardsdoublearrow,U+21D1ISOamsa-->

　　{"rArr","8658"},//rightwardsdoublearrow,U+21D2ISOtech-->

　　//<!--ISO10646doesnotsaythisisthe'implies'characterbutdoesnot

　　//haveanothercharacterwiththisfunctionso?rArrcanbeusedfor

　　//'implies'asISOtechsuggests-->

　　{"dArr","8659"},//downwardsdoublearrow,U+21D3ISOamsa-->

　　{"hArr","8660"},//leftrightdoublearrow,U+21D4ISOamsa-->

　　//<!--MathematicalOperators-->

　　{"forall","8704"},//forall,U+2200ISOtech-->

　　{"part","8706"},//partialdifferential,U+2202ISOtech-->

　　{"exist","8707"},//thereexists,U+2203ISOtech-->

　　{"empty","8709"},//emptyset=nullset=diameter,U+2205ISOamso-->

　　{"nabla","8711"},//nabla=backwarddifference,U+2207ISOtech-->

　　{"isin","8712"},//elementof,U+2208ISOtech-->

　　{"notin","8713"},//notanelementof,U+2209ISOtech-->

　　{"ni","8715"},//containsasmember,U+220BISOtech-->

　　//<!--shouldtherebeamorememorablenamethan'ni'?-->

　　{"prod","8719"},//n-aryproduct=productsign,U+220FISOamsb-->

　　//<!--prodisNOTthesamecharacterasU+03A0'greekcapitalletterpi'

　　//thoughthesameglyphmightbeusedforboth-->

　　{"sum","8721"},//n-arysummation,U+2211ISOamsb-->

　　//<!--sumisNOTthesamecharacterasU+03A3'greekcapitallettersigma'

　　//thoughthesameglyphmightbeusedforboth-->

　　{"minus","8722"},//minussign,U+2212ISOtech-->

　　{"lowast","8727"},//asteriskoperator,U+2217ISOtech-->

　　{"radic","8730"},//squareroot=radicalsign,U+221AISOtech-->

　　{"prop","8733"},//proportionalto,U+221DISOtech-->

　　{"infin","8734"},//infinity,U+221EISOtech-->

　　{"ang","8736"},//angle,U+2220ISOamso-->

　　{"and","8743"},//logicaland=wedge,U+2227ISOtech-->

　　{"or","8744"},//logicalor=vee,U+2228ISOtech-->

　　{"cap","8745"},//intersection=cap,U+2229ISOtech-->

　　{"cup","8746"},//union=cup,U+222AISOtech-->

　　{"int","8747"},//integral,U+222BISOtech-->

　　{"there4","8756"},//therefore,U+2234ISOtech-->

　　{"sim","8764"},//tildeoperator=varieswith=similarto,U+223CISOtech-->

　　//<!--tildeoperatorisNOTthesamecharacterasthetilde,U+007E,although

　　//thesameglyphmightbeusedtorepresentboth-->

　　{"cong","8773"},//approximatelyequalto,U+2245ISOtech-->

　　{"asymp","8776"},//almostequalto=asymptoticto,U+2248ISOamsr-->

　　{"ne","8800"},//notequalto,U+2260ISOtech-->

　　{"equiv","8801"},//identicalto,U+2261ISOtech-->

　　{"le","8804"},//less-thanorequalto,U+2264ISOtech-->

　　{"ge","8805"},//greater-thanorequalto,U+2265ISOtech-->

　　{"sub","8834"},//subsetof,U+2282ISOtech-->

　　{"sup","8835"},//supersetof,U+2283ISOtech-->

　　//<!--notethatnsup,'notasupersetof,U+2283'isnotcoveredbythe

　　//Symbolfontencodingandisnotincluded.Shoulditbe,forsymmetry?

　　//ItisinISOamsn--><!ENTITYnsub","8836"},

　　//notasubsetof,U+2284ISOamsn-->

　　{"sube","8838"},//subsetoforequalto,U+2286ISOtech-->

　　{"supe","8839"},//supersetoforequalto,U+2287ISOtech-->

　　{"oplus","8853"},//circledplus=directsum,U+2295ISOamsb-->

　　{"otimes","8855"},//circledtimes=vectorproduct,U+2297ISOamsb-->

　　{"perp","8869"},//uptack=orthogonalto=perpendicular,U+22A5ISOtech-->

　　{"sdot","8901"},//dotoperator,U+22C5ISOamsb-->

　　//<!--dotoperatorisNOTthesamecharacterasU+00B7middledot-->

　　//<!--MiscellaneousTechnical-->

　　{"lceil","8968"},//leftceiling=aplupstile,U+2308ISOamsc-->

　　{"rceil","8969"},//rightceiling,U+2309ISOamsc-->

　　{"lfloor","8970"},//leftfloor=apldownstile,U+230AISOamsc-->

　　{"rfloor","8971"},//rightfloor,U+230BISOamsc-->

　　{"lang","9001"},//left-pointinganglebracket=bra,U+2329ISOtech-->

　　//<!--langisNOTthesamecharacterasU+003C'lessthan'orU+2039'singleleft-pointinganglequotation

　　//mark'-->

　　{"rang","9002"},//right-pointinganglebracket=ket,U+232AISOtech-->

　　//<!--rangisNOTthesamecharacterasU+003E'greaterthan'orU+203A

　　//'singleright-pointinganglequotationmark'-->

　　//<!--GeometricShapes-->

　　{"loz","9674"},//lozenge,U+25CAISOpub-->

　　//<!--MiscellaneousSymbols-->

　　{"spades","9824"},//blackspadesuit,U+2660ISOpub-->

　　//<!--blackhereseemstomeanfilledasopposedtohollow-->

　　{"clubs","9827"},//blackclubsuit=shamrock,U+2663ISOpub-->

　　{"hearts","9829"},//blackheartsuit=valentine,U+2665ISOpub-->

　　{"diams","9830"},//blackdiamondsuit,U+2666ISOpub-->

　　//<!--LatinExtended-A-->

　　{"OElig","338"},//--latincapitalligatureOE,U+0152ISOlat2-->

　　{"oelig","339"},//--latinsmallligatureoe,U+0153ISOlat2-->

　　//<!--ligatureisamisnomer,thisisaseparatecharacterinsomelanguages-->

　　{"Scaron","352"},//--latincapitalletterSwithcaron,U+0160ISOlat2-->

　　{"scaron","353"},//--latinsmallletterswithcaron,U+0161ISOlat2-->

　　{"Yuml","376"},//--latincapitalletterYwithdiaeresis,U+0178ISOlat2-->

　　//<!--SpacingModifierLetters-->

　　{"circ","710"},//--modifierlettercircumflexaccent,U+02C6ISOpub-->

　　{"tilde","732"},//smalltilde,U+02DCISOdia-->

　　//<!--GeneralPunctuation-->

　　{"ensp","8194"},//enspace,U+2002ISOpub-->

　　{"emsp","8195"},//emspace,U+2003ISOpub-->

　　{"thinsp","8201"},//thinspace,U+2009ISOpub-->

　　{"zwnj","8204"},//zerowidthnon-joiner,U+200CNEWRFC2070-->

　　{"zwj","8205"},//zerowidthjoiner,U+200DNEWRFC2070-->

　　{"lrm","8206"},//left-to-rightmark,U+200ENEWRFC2070-->

　　{"rlm","8207"},//right-to-leftmark,U+200FNEWRFC2070-->

　　{"ndash","8211"},//endash,U+2013ISOpub-->

　　{"mdash","8212"},//emdash,U+2014ISOpub-->

　　{"lsquo","8216"},//leftsinglequotationmark,U+2018ISOnum-->

　　{"rsquo","8217"},//rightsinglequotationmark,U+2019ISOnum-->

　　{"sbquo","8218"},//singlelow-9quotationmark,U+201ANEW-->

　　{"ldquo","8220"},//leftdoublequotationmark,U+201CISOnum-->

　　{"rdquo","8221"},//rightdoublequotationmark,U+201DISOnum-->

　　{"bdquo","8222"},//doublelow-9quotationmark,U+201ENEW-->

　　{"dagger","8224"},//dagger,U+2020ISOpub-->

　　{"Dagger","8225"},//doubledagger,U+2021ISOpub-->

　　{"permil","8240"},//permillesign,U+2030ISOtech-->

　　{"lsaquo","8249"},//singleleft-pointinganglequotationmark,U+2039ISOproposed-->

　　//<!--lsaquoisproposedbutnotyetISOstandardized-->

　　{"rsaquo","8250"},//singleright-pointinganglequotationmark,U+203AISOproposed-->

　　//<!--rsaquoisproposedbutnotyetISOstandardized-->

　　{"euro","8364"},//--eurosign,U+20ACNEW-->

　　};

感謝各位的閱讀，以上就是“html的轉義字符然后通過代碼識別”的內容了，經過本文的學習后，相信大家對html的轉義字符然后通過代碼識別這一問題有了更深刻的體會，具體使用情況還需要大家實踐驗證。這里是億速云，小編將為大家推送更多相關知識點的文章，歡迎關注！