我正在尝试从字符串中剥离除以下字符之外的所有字符：
- 字母数字字符
- 美元符号（
$） - 下芯（
_） - 代码点
U+0080和U+FFFF之间的Unicode字符
通过这样做，我得到了前三个条件：
preg_replace('/[^a-zA-Zd$_]+/', '', $foo);
如何匹配第四个条件？我考虑过使用X，但必须有比列出65000多个字符更好的方法。
您可以使用：
$foo = preg_replace('/[^w$x{0080}-x{FFFF}]+/u', '', $foo);
w-相当于[a-zA-Z0-9_]x{0080}-x{FFFF}匹配码点之间的字符U+0080andU+FFFF`- 正则表达式中支持unicode的
/u
现代化的答案。
如果只排除代码点U+80-U+FFFF，那将是不明智的假定Unicode范围扩展到U+10FFFF。
如今，它涵盖了许多超过16位bmp范围的字符。
我将向您展示如何在您想要的范围内完成
utf-16或utf-8/32，您可以控制也可以不控制。
UTF-16
# UTF-16 regex ; equavelent UTF-8/32 regex (?![x{80}-x{FFFF}])[$w]
(?!
(?:
[x{80}-x{D7FF}x{E000}-x{FFFF}]
|
[x{D800}-x{DBFF}]
(?! [x{DC00}-x{DFFF}] )
|
[x{DC00}-x{DFFF}]
(?<! [x{D800}-x{DBFF}] [Ss] )
)
)
[$w]
# Output --------------------------------
# 77,905 Unicode characters
# UTF-16 regex equivalent (using codepoints)
(?:
[x{24}x{30}-x{39}x{41}-x{5A}x{5F}x{61}-x{7A}]
|
(?:
x{D800} [x{DC00}-x{DC0B}x{DC0D}-x{DC26}x{DC28}-x{DC3A}x{DC3C}-x{DC3D}x{DC3F}-x{DC4D}x{DC50}-x{DC5D}x{DC80}-x{DCFA}x{DDFD}x{DE80}-x{DE9C}x{DEA0}-x{DED0}x{DEE0}x{DF00}-x{DF1F}x{DF2D}-x{DF40}x{DF42}-x{DF49}x{DF50}-x{DF7A}x{DF80}-x{DF9D}x{DFA0}-x{DFC3}x{DFC8}-x{DFCF}]
| x{D801} [x{DC00}-x{DC9D}x{DCA0}-x{DCA9}x{DCB0}-x{DCD3}x{DCD8}-x{DCFB}x{DD00}-x{DD27}x{DD30}-x{DD63}x{DE00}-x{DF36}x{DF40}-x{DF55}x{DF60}-x{DF67}]
| x{D802} [x{DC00}-x{DC05}x{DC08}x{DC0A}-x{DC35}x{DC37}-x{DC38}x{DC3C}x{DC3F}-x{DC55}x{DC60}-x{DC76}x{DC80}-x{DC9E}x{DCE0}-x{DCF2}x{DCF4}-x{DCF5}x{DD00}-x{DD15}x{DD20}-x{DD39}x{DD80}-x{DDB7}x{DDBE}-x{DDBF}x{DE00}-x{DE03}x{DE05}-x{DE06}x{DE0C}-x{DE13}x{DE15}-x{DE17}x{DE19}-x{DE35}x{DE38}-x{DE3A}x{DE3F}x{DE60}-x{DE7C}x{DE80}-x{DE9C}x{DEC0}-x{DEC7}x{DEC9}-x{DEE6}x{DF00}-x{DF35}x{DF40}-x{DF55}x{DF60}-x{DF72}x{DF80}-x{DF91}]
| x{D803} [x{DC00}-x{DC48}x{DC80}-x{DCB2}x{DCC0}-x{DCF2}x{DD00}-x{DD27}x{DD30}-x{DD39}x{DF00}-x{DF1C}x{DF27}x{DF30}-x{DF50}x{DFE0}-x{DFF6}]
| x{D804} [x{DC01}x{DC03}-x{DC46}x{DC66}-x{DC6F}x{DC7F}-x{DC81}x{DC83}-x{DCAF}x{DCB3}-x{DCB6}x{DCB9}-x{DCBA}x{DCD0}-x{DCE8}x{DCF0}-x{DCF9}x{DD00}-x{DD2B}x{DD2D}-x{DD34}x{DD36}-x{DD3F}x{DD44}x{DD50}-x{DD73}x{DD76}x{DD80}-x{DD81}x{DD83}-x{DDB2}x{DDB6}-x{DDBE}x{DDC1}-x{DDC4}x{DDC9}-x{DDCC}x{DDD0}-x{DDDA}x{DDDC}x{DE00}-x{DE11}x{DE13}-x{DE2B}x{DE2F}-x{DE31}x{DE34}x{DE36}-x{DE37}x{DE3E}x{DE80}-x{DE86}x{DE88}x{DE8A}-x{DE8D}x{DE8F}-x{DE9D}x{DE9F}-x{DEA8}x{DEB0}-x{DEDF}x{DEE3}-x{DEEA}x{DEF0}-x{DEF9}x{DF00}-x{DF01}x{DF05}-x{DF0C}x{DF0F}-x{DF10}x{DF13}-x{DF28}x{DF2A}-x{DF30}x{DF32}-x{DF33}x{DF35}-x{DF39}x{DF3B}-x{DF3D}x{DF40}x{DF50}x{DF5D}-x{DF61}x{DF66}-x{DF6C}x{DF70}-x{DF74}]
| x{D805} [x{DC00}-x{DC34}x{DC38}-x{DC3F}x{DC42}-x{DC44}x{DC46}-x{DC4A}x{DC50}-x{DC59}x{DC5E}-x{DC5F}x{DC80}-x{DCAF}x{DCB3}-x{DCB8}x{DCBA}x{DCBF}-x{DCC0}x{DCC2}-x{DCC5}x{DCC7}x{DCD0}-x{DCD9}x{DD80}-x{DDAE}x{DDB2}-x{DDB5}x{DDBC}-x{DDBD}x{DDBF}-x{DDC0}x{DDD8}-x{DDDD}x{DE00}-x{DE2F}x{DE33}-x{DE3A}x{DE3D}x{DE3F}-x{DE40}x{DE44}x{DE50}-x{DE59}x{DE80}-x{DEAB}x{DEAD}x{DEB0}-x{DEB5}x{DEB7}-x{DEB8}x{DEC0}-x{DEC9}x{DF00}-x{DF1A}x{DF1D}-x{DF1F}x{DF22}-x{DF25}x{DF27}-x{DF2B}x{DF30}-x{DF39}]
| x{D806} [x{DC00}-x{DC2B}x{DC2F}-x{DC37}x{DC39}-x{DC3A}x{DCA0}-x{DCE9}x{DCFF}x{DDA0}-x{DDA7}x{DDAA}-x{DDD0}x{DDD4}-x{DDD7}x{DDDA}-x{DDDB}x{DDE0}-x{DDE1}x{DDE3}x{DE00}-x{DE38}x{DE3A}-x{DE3E}x{DE47}x{DE50}-x{DE56}x{DE59}-x{DE96}x{DE98}-x{DE99}x{DE9D}x{DEC0}-x{DEF8}]
| x{D807} [x{DC00}-x{DC08}x{DC0A}-x{DC2E}x{DC30}-x{DC36}x{DC38}-x{DC3D}x{DC3F}-x{DC40}x{DC50}-x{DC59}x{DC72}-x{DC8F}x{DC92}-x{DCA7}x{DCAA}-x{DCB0}x{DCB2}-x{DCB3}x{DCB5}-x{DCB6}x{DD00}-x{DD06}x{DD08}-x{DD09}x{DD0B}-x{DD36}x{DD3A}x{DD3C}-x{DD3D}x{DD3F}-x{DD47}x{DD50}-x{DD59}x{DD60}-x{DD65}x{DD67}-x{DD68}x{DD6A}-x{DD89}x{DD90}-x{DD91}x{DD95}x{DD97}-x{DD98}x{DDA0}-x{DDA9}x{DEE0}-x{DEF4}]
| x{D808} [x{DC00}-x{DF99}]
| x{D809} [x{DC80}-x{DD43}]
| x{D80C} [x{DC00}-x{DFFF}]
| x{D80D} [x{DC00}-x{DC2E}]
| x{D811} [x{DC00}-x{DE46}]
| x{D81A} [x{DC00}-x{DE38}x{DE40}-x{DE5E}x{DE60}-x{DE69}x{DED0}-x{DEED}x{DEF0}-x{DEF4}x{DF00}-x{DF36}x{DF40}-x{DF43}x{DF50}-x{DF59}x{DF63}-x{DF77}x{DF7D}-x{DF8F}]
| x{D81B} [x{DE40}-x{DE7F}x{DF00}-x{DF4A}x{DF4F}-x{DF50}x{DF8F}-x{DF9F}x{DFE0}-x{DFE1}x{DFE3}]
| [x{D81C}-x{D820}] [x{DC00}-x{DFFF}]
| x{D821} [x{DC00}-x{DFF7}]
| x{D822} [x{DC00}-x{DEF2}]
| x{D82C} [x{DC00}-x{DD1E}x{DD50}-x{DD52}x{DD64}-x{DD67}x{DD70}-x{DEFB}]
| x{D82F} [x{DC00}-x{DC6A}x{DC70}-x{DC7C}x{DC80}-x{DC88}x{DC90}-x{DC99}x{DC9D}-x{DC9E}]
| x{D834} [x{DD67}-x{DD69}x{DD7B}-x{DD82}x{DD85}-x{DD8B}x{DDAA}-x{DDAD}x{DE42}-x{DE44}]
| x{D835} [x{DC00}-x{DC54}x{DC56}-x{DC9C}x{DC9E}-x{DC9F}x{DCA2}x{DCA5}-x{DCA6}x{DCA9}-x{DCAC}x{DCAE}-x{DCB9}x{DCBB}x{DCBD}-x{DCC3}x{DCC5}-x{DD05}x{DD07}-x{DD0A}x{DD0D}-x{DD14}x{DD16}-x{DD1C}x{DD1E}-x{DD39}x{DD3B}-x{DD3E}x{DD40}-x{DD44}x{DD46}x{DD4A}-x{DD50}x{DD52}-x{DEA5}x{DEA8}-x{DEC0}x{DEC2}-x{DEDA}x{DEDC}-x{DEFA}x{DEFC}-x{DF14}x{DF16}-x{DF34}x{DF36}-x{DF4E}x{DF50}-x{DF6E}x{DF70}-x{DF88}x{DF8A}-x{DFA8}x{DFAA}-x{DFC2}x{DFC4}-x{DFCB}x{DFCE}-x{DFFF}]
| x{D836} [x{DE00}-x{DE36}x{DE3B}-x{DE6C}x{DE75}x{DE84}x{DE9B}-x{DE9F}x{DEA1}-x{DEAF}]
| x{D838} [x{DC00}-x{DC06}x{DC08}-x{DC18}x{DC1B}-x{DC21}x{DC23}-x{DC24}x{DC26}-x{DC2A}x{DD00}-x{DD2C}x{DD30}-x{DD3D}x{DD40}-x{DD49}x{DD4E}x{DEC0}-x{DEF9}]
| x{D83A} [x{DC00}-x{DCC4}x{DCD0}-x{DCD6}x{DD00}-x{DD4B}x{DD50}-x{DD59}]
| x{D83B} [x{DE00}-x{DE03}x{DE05}-x{DE1F}x{DE21}-x{DE22}x{DE24}x{DE27}x{DE29}-x{DE32}x{DE34}-x{DE37}x{DE39}x{DE3B}x{DE42}x{DE47}x{DE49}x{DE4B}x{DE4D}-x{DE4F}x{DE51}-x{DE52}x{DE54}x{DE57}x{DE59}x{DE5B}x{DE5D}x{DE5F}x{DE61}-x{DE62}x{DE64}x{DE67}-x{DE6A}x{DE6C}-x{DE72}x{DE74}-x{DE77}x{DE79}-x{DE7C}x{DE7E}x{DE80}-x{DE89}x{DE8B}-x{DE9B}x{DEA1}-x{DEA3}x{DEA5}-x{DEA9}x{DEAB}-x{DEBB}]
| [x{D840}-x{D868}] [x{DC00}-x{DFFF}]
| x{D869} [x{DC00}-x{DED6}x{DF00}-x{DFFF}]
| [x{D86A}-x{D86C}] [x{DC00}-x{DFFF}]
| x{D86D} [x{DC00}-x{DF34}x{DF40}-x{DFFF}]
| x{D86E} [x{DC00}-x{DC1D}x{DC20}-x{DFFF}]
| [x{D86F}-x{D872}] [x{DC00}-x{DFFF}]
| x{D873} [x{DC00}-x{DEA1}x{DEB0}-x{DFFF}]
| [x{D874}-x{D879}] [x{DC00}-x{DFFF}]
| x{D87A} [x{DC00}-x{DFE0}]
| x{D87E} [x{DC00}-x{DE1D}]
| x{DB40} [x{DD00}-x{DDEF}]
)
)
UTF-8/32
# UTF-8/32 regex ;
(?! [x{80}-x{FFFF}] )
[$w]
# Output --------------------------------
# 77,905 Unicode characters
# UTF-8 / 32 regex equivalent (using codepoints)
(?:
[x{24}x{30}-x{39}x{41}-x{5A}x{5F}x{61}-x{7A}x{10000}-x{1000B}x{1000D}-x{10026}x{10028}-x{1003A}x{1003C}-x{1003D}x{1003F}-x{1004D}x{10050}-x{1005D}x{10080}-x{100FA}x{101FD}x{10280}-x{1029C}x{102A0}-x{102D0}x{102E0}x{10300}-x{1031F}x{1032D}-x{10340}x{10342}-x{10349}x{10350}-x{1037A}x{10380}-x{1039D}x{103A0}-x{103C3}x{103C8}-x{103CF}x{10400}-x{1049D}x{104A0}-x{104A9}x{104B0}-x{104D3}x{104D8}-x{104FB}x{10500}-x{10527}x{10530}-x{10563}x{10600}-x{10736}x{10740}-x{10755}x{10760}-x{10767}x{10800}-x{10805}x{10808}x{1080A}-x{10835}x{10837}-x{10838}x{1083C}x{1083F}-x{10855}x{10860}-x{10876}x{10880}-x{1089E}x{108E0}-x{108F2}x{108F4}-x{108F5}x{10900}-x{10915}x{10920}-x{10939}x{10980}-x{109B7}x{109BE}-x{109BF}x{10A00}-x{10A03}x{10A05}-x{10A06}x{10A0C}-x{10A13}x{10A15}-x{10A17}x{10A19}-x{10A35}x{10A38}-x{10A3A}x{10A3F}x{10A60}-x{10A7C}x{10A80}-x{10A9C}x{10AC0}-x{10AC7}x{10AC9}-x{10AE6}x{10B00}-x{10B35}x{10B40}-x{10B55}x{10B60}-x{10B72}x{10B80}-x{10B91}x{10C00}-x{10C48}x{10C80}-x{10CB2}x{10CC0}-x{10CF2}x{10D00}-x{10D27}x{10D30}-x{10D39}x{10F00}-x{10F1C}x{10F27}x{10F30}-x{10F50}x{10FE0}-x{10FF6}x{11001}x{11003}-x{11046}x{11066}-x{1106F}x{1107F}-x{11081}x{11083}-x{110AF}x{110B3}-x{110B6}x{110B9}-x{110BA}x{110D0}-x{110E8}x{110F0}-x{110F9}x{11100}-x{1112B}x{1112D}-x{11134}x{11136}-x{1113F}x{11144}x{11150}-x{11173}x{11176}x{11180}-x{11181}x{11183}-x{111B2}x{111B6}-x{111BE}x{111C1}-x{111C4}x{111C9}-x{111CC}x{111D0}-x{111DA}x{111DC}x{11200}-x{11211}x{11213}-x{1122B}x{1122F}-x{11231}x{11234}x{11236}-x{11237}x{1123E}x{11280}-x{11286}x{11288}x{1128A}-x{1128D}x{1128F}-x{1129D}x{1129F}-x{112A8}x{112B0}-x{112DF}x{112E3}-x{112EA}x{112F0}-x{112F9}x{11300}-x{11301}x{11305}-x{1130C}x{1130F}-x{11310}x{11313}-x{11328}x{1132A}-x{11330}x{11332}-x{11333}x{11335}-x{11339}x{1133B}-x{1133D}x{11340}x{11350}x{1135D}-x{11361}x{11366}-x{1136C}x{11370}-x{11374}x{11400}-x{11434}x{11438}-x{1143F}x{11442}-x{11444}x{11446}-x{1144A}x{11450}-x{11459}x{1145E}-x{1145F}x{11480}-x{114AF}x{114B3}-x{114B8}x{114BA}x{114BF}-x{114C0}x{114C2}-x{114C5}x{114C7}x{114D0}-x{114D9}x{11580}-x{115AE}x{115B2}-x{115B5}x{115BC}-x{115BD}x{115BF}-x{115C0}x{115D8}-x{115DD}x{11600}-x{1162F}x{11633}-x{1163A}x{1163D}x{1163F}-x{11640}x{11644}x{11650}-x{11659}x{11680}-x{116AB}x{116AD}x{116B0}-x{116B5}x{116B7}-x{116B8}x{116C0}-x{116C9}x{11700}-x{1171A}x{1171D}-x{1171F}x{11722}-x{11725}x{11727}-x{1172B}x{11730}-x{11739}x{11800}-x{1182B}x{1182F}-x{11837}x{11839}-x{1183A}x{118A0}-x{118E9}x{118FF}x{119A0}-x{119A7}x{119AA}-x{119D0}x{119D4}-x{119D7}x{119DA}-x{119DB}x{119E0}-x{119E1}x{119E3}x{11A00}-x{11A38}x{11A3A}-x{11A3E}x{11A47}x{11A50}-x{11A56}x{11A59}-x{11A96}x{11A98}-x{11A99}x{11A9D}x{11AC0}-x{11AF8}x{11C00}-x{11C08}x{11C0A}-x{11C2E}x{11C30}-x{11C36}x{11C38}-x{11C3D}x{11C3F}-x{11C40}x{11C50}-x{11C59}x{11C72}-x{11C8F}x{11C92}-x{11CA7}x{11CAA}-x{11CB0}x{11CB2}-x{11CB3}x{11CB5}-x{11CB6}x{11D00}-x{11D06}x{11D08}-x{11D09}x{11D0B}-x{11D36}x{11D3A}x{11D3C}-x{11D3D}x{11D3F}-x{11D47}x{11D50}-x{11D59}x{11D60}-x{11D65}x{11D67}-x{11D68}x{11D6A}-x{11D89}x{11D90}-x{11D91}x{11D95}x{11D97}-x{11D98}x{11DA0}-x{11DA9}x{11EE0}-x{11EF4}x{12000}-x{12399}x{12480}-x{12543}x{13000}-x{1342E}x{14400}-x{14646}x{16800}-x{16A38}x{16A40}-x{16A5E}x{16A60}-x{16A69}x{16AD0}-x{16AED}x{16AF0}-x{16AF4}x{16B00}-x{16B36}x{16B40}-x{16B43}x{16B50}-x{16B59}x{16B63}-x{16B77}x{16B7D}-x{16B8F}x{16E40}-x{16E7F}x{16F00}-x{16F4A}x{16F4F}-x{16F50}x{16F8F}-x{16F9F}x{16FE0}-x{16FE1}x{16FE3}x{17000}-x{187F7}x{18800}-x{18AF2}x{1B000}-x{1B11E}x{1B150}-x{1B152}x{1B164}-x{1B167}x{1B170}-x{1B2FB}x{1BC00}-x{1BC6A}x{1BC70}-x{1BC7C}x{1BC80}-x{1BC88}x{1BC90}-x{1BC99}x{1BC9D}-x{1BC9E}x{1D167}-x{1D169}x{1D17B}-x{1D182}x{1D185}-x{1D18B}x{1D1AA}-x{1D1AD}x{1D242}-x{1D244}x{1D400}-x{1D454}x{1D456}-x{1D49C}x{1D49E}-x{1D49F}x{1D4A2}x{1D4A5}-x{1D4A6}x{1D4A9}-x{1D4AC}x{1D4AE}-x{1D4B9}x{1D4BB}x{1D4BD}-x{1D4C3}x{1D4C5}-x{1D505}x{1D507}-x{1D50A}x{1D50D}-x{1D514}x{1D516}-x{1D51C}x{1D51E}-x{1D539}x{1D53B}-x{1D53E}x{1D540}-x{1D544}x{1D546}x{1D54A}-x{1D550}x{1D552}-x{1D6A5}x{1D6A8}-x{1D6C0}x{1D6C2}-x{1D6DA}x{1D6DC}-x{1D6FA}x{1D6FC}-x{1D714}x{1D716}-x{1D734}x{1D736}-x{1D74E}x{1D750}-x{1D76E}x{1D770}-x{1D788}x{1D78A}-x{1D7A8}x{1D7AA}-x{1D7C2}x{1D7C4}-x{1D7CB}x{1D7CE}-x{1D7FF}x{1DA00}-x{1DA36}x{1DA3B}-x{1DA6C}x{1DA75}x{1DA84}x{1DA9B}-x{1DA9F}x{1DAA1}-x{1DAAF}x{1E000}-x{1E006}x{1E008}-x{1E018}x{1E01B}-x{1E021}x{1E023}-x{1E024}x{1E026}-x{1E02A}x{1E100}-x{1E12C}x{1E130}-x{1E13D}x{1E140}-x{1E149}x{1E14E}x{1E2C0}-x{1E2F9}x{1E800}-x{1E8C4}x{1E8D0}-x{1E8D6}x{1E900}-x{1E94B}x{1E950}-x{1E959}x{1EE00}-x{1EE03}x{1EE05}-x{1EE1F}x{1EE21}-x{1EE22}x{1EE24}x{1EE27}x{1EE29}-x{1EE32}x{1EE34}-x{1EE37}x{1EE39}x{1EE3B}x{1EE42}x{1EE47}x{1EE49}x{1EE4B}x{1EE4D}-x{1EE4F}x{1EE51}-x{1EE52}x{1EE54}x{1EE57}x{1EE59}x{1EE5B}x{1EE5D}x{1EE5F}x{1EE61}-x{1EE62}x{1EE64}x{1EE67}-x{1EE6A}x{1EE6C}-x{1EE72}x{1EE74}-x{1EE77}x{1EE79}-x{1EE7C}x{1EE7E}x{1EE80}-x{1EE89}x{1EE8B}-x{1EE9B}x{1EEA1}-x{1EEA3}x{1EEA5}-x{1EEA9}x{1EEAB}-x{1EEBB}x{20000}-x{2A6D6}x{2A700}-x{2B734}x{2B740}-x{2B81D}x{2B820}-x{2CEA1}x{2CEB0}-x{2EBE0}x{2F800}-x{2FA1D}x{E0100}-x{E01EF}]
)
最后，最简单的，将范围扩展到U+10FFFF
# UTF-8/32 regex ;
(?! [x{80}-x{10FFFF}] )
[$w]
# Output --------------------------------
# 64 Unicode characters
# UTF-8 / 16/ 32 regex equivalent (using codepoints)
[x{24}x{30}-x{39}x{41}-x{5A}x{5F}x{61}-x{7A}]
# Codepoint -> character substitution
[$0-9A-Z_a-z]
如果您真的想为MySQL默认排序规则（utf8_general_ci）清理字符串，那么仅仅删除表情符号是不够的。utf8_general_ci对应于字符集utf8/utf8mb3，它只支持0x000到0xFFFF（基本多语言平面）的范围。因此，我建议删除任何代码超过0xFFFF的字符（0x10FFFF/16:SPUA-B，我认为是迄今为止已知的最大字符，根据https://en.wikipedia.org/wiki/Plane_（Unicode）
function removeNonBasicMultilingualPlane(string $text): string
{
return preg_replace('/[x{10000}-x{10FFFF}]/u', '', $text);
}