Editing Regular expression in Mandarin

透過正規表示法 (Regular Expression) 處理文字檔時，可以快速地搜尋或取代符合特定規則的字串。以每行為單位，進行字串處理<ref>[http://linux.vbird.org/linux_basic/0330regularex.php 鳥哥的 Linux 私房菜 -- 正規表示法 (regular expression, RE) 與文件格式化處理]</ref>。 正規表示法 又稱正規表示式、正規表達式、正則表達式、正規表示法、正規運算式、規則運算式、常規表示法<ref>[https://zh.wikipedia.org/wiki/%E6%AD%A3%E5%88%99%E8%A1%A8%E8%BE%BE%E5%BC%8F 正規表示式 - 維基百科，自由的百科全書]</ref>。

{{Raise hand | text = 有問題嗎？可以利用提供解說的[[Regular_expression#Regular_expression_online_tools | 線上工具]]，嘗試自己除錯。 也可以到[http://www.ptt.cc/bbs/RegExp/index.html 看板 RegExp 文章列表 - 批踢踢實業坊]或其他[[問答服務]]詢問。 }}

== 快速查表 ==
說明: (1) sample 藍色網底處代表符合規則的文字、(2) 同一文字規則可以有多種表示法
<table border="1" style="width:100%" class="wikitable">
<tr >
<th style="background-color: #E0E0E0;"> 文字規則 </th>
<th style="background-color: #E0E0E0; width:260px;"> sample </th>
<th style="background-color: #9c9ca3;"> 對立的文字規則 </th>
<th style="background-color: #9c9ca3; width:260px;"> sample</th>
</tr>
<tr>
<td> 任意一個文字(包含空白，但不包含換行符號) <br /> {{kbd | key = <nowiki>.</nowiki>}} </td>
<td><span style="background:#C6E3FF">W</span>hat Does the Fox Say? 12 狐狸怎叫 34</td>
<td></td>
<td></td>
</tr>
<tr>
<td> 任意文字(包含空白)，出現1次或0次 <br /> {{kbd | key = <nowiki>.?</nowiki>}} = {{kbd | key = <nowiki>.{0,1}</nowiki>}}</td>
<td><span style="background:#C6E3FF">W</span>hat Does the Fox Say? 12 狐狸怎叫 34</td>
<td></td>
<td></td>
</tr>
<tr>
<td> 任意次的多個文字(包含空白) <br /> {{kbd | key = <nowiki>.*</nowiki>}} ={{kbd | key = <nowiki> .{0,}</nowiki>}}</td>
<td><span style="background:#C6E3FF">What Does the Fox Say? 12 狐狸怎叫 34</span></td>
<td></td>
<td></td>
</tr>
<tr>
<td> 任意次的文字(包含空白)，至少出現1次 <br /> {{kbd | key = <nowiki>.+</nowiki>}} = {{kbd | key = <nowiki>.{1,}</nowiki>}}</td>
<td><span style="background:#C6E3FF">What Does the Fox Say? 12 狐狸怎叫 34</span></td>
<td></td>
<td></td>
</tr>
<tr>
<td> 任意次的空白或換行符號 (至少出現1次的空白或換行符號)  <br /> {{kbd | key = <nowiki>\s+</nowiki>}} </td>
<td>What<span style="background:#C6E3FF"> </span>Does the Fox Say? 12 狐狸怎叫 34</td>
<td>任意多個文字(不包含空白或換行符號) <br /> {{kbd | key = <nowiki>[^\s]+</nowiki>}} ={{kbd | key = <nowiki> [^\s]{1,}</nowiki>}} = {{kbd | key = <nowiki> [\S]+</nowiki>}} = {{kbd | key = <nowiki>[^ ]+</nowiki>}}</td>
<td><span style="background:#C6E3FF">What</span> Does the Fox Say? 12 狐狸怎叫 34</td>
</tr>
<tr>
<td> 任意次的 ASCII character (包含英文、數字和空白) [http://regexr.com/3aom2 demo]<ref>[http://www.asciitable.com/ Ascii Table - ASCII character codes and html, octal, hex and decimal chart conversion]</ref> <br /> {{kbd | key = <nowiki>[\x00-\x80]+</nowiki>}} 或 {{kbd | key = <nowiki>[[:ascii:]]+</nowiki>}}<ref>[https://stackoverflow.com/questions/24903140/regex-for-any-english-ascii-character-including-special-characters php - Regex for Any English ASCII Character Including Special Characters - Stack Overflow]</ref></td>
<td><span style="background:#C6E3FF">What Does the Fox Say? 12</span> 狐狸怎叫 34</td>
<td>非 ASCII，即中文出現任意次<br /> {{kbd | key = <nowiki>[^\x00-\x80]+</nowiki>}}</td>
<td>What Does the Fox Say? 12 <span style="background:#C6E3FF">狐狸怎叫</span> 34</td>
</tr>
<tr>
<td> 任意次的大小寫英文、數字和底線符號( _ ) (不包含空白) ([https://regex101.com/r/gIKB6a/1 demo])<br /> {{kbd | key = <nowiki>[\w]+</nowiki>}} = {{kbd | key = <nowiki>[a-zA-Z0-9_]+</nowiki>}} <br /> PHP 加上 {{kbd | key =u}} 修飾語，則可支援中文字 </td>
<td><span style="background:#C6E3FF">What</span> <span style="background:#C6E3FF">Does</span> <span style="background:#C6E3FF">the</span> <span style="background:#C6E3FF">Fox</span> <span style="background:#C6E3FF">Say</span>? <span style="background:#C6E3FF">12</span> 狐狸怎叫 <span style="background:#C6E3FF">_34</span></td>
<td> 任意次的不是英文、數字和底線符號( _ )的文字 <br /> {{kbd | key = <nowiki>\W+</nowiki>}} = {{kbd | key = <nowiki>[^a-zA-Z0-9_]+</nowiki>}}</td>
<td>[http://regexr.com/3bk4v demo]</td>
</tr>
<tr>
<td> 任意次的數字(不包含空白) <br /> {{kbd | key = <nowiki>[\d]+</nowiki>}} = {{kbd | key = <nowiki>[0-9]+</nowiki>}}</td>
<td>What Does the Fox Say? <span style="background:#C6E3FF">12</span> 狐狸怎叫 34</td>
<td>不包含數字的任意次文字(包含空白  <br /> {{kbd | key = <nowiki>[^\d]+</nowiki>}} = {{kbd | key = <nowiki>[^0-9]+</nowiki>}} = {{kbd | key = <nowiki>\D+</nowiki>}} </td>
<td><span style="background:#C6E3FF">What Does the Fox Say? </span>12 狐狸怎叫 34</td>
</tr>
<tr>
<td> 任意次的中文字 <br /> {{kbd | key = <nowiki>[\p{Han}]+</nowiki>}} ([https://regex101.com/r/UYkdml/1 demo]、[[Regular expression#尋找中文、非英文的文字 | 詳細說明]])</td>
<td>What Does the Fox Say? 12 <span style="background:#C6E3FF">狐狸怎叫</span> 34</td>
<td>不包含中文字的任意次文字  <br /> {{kbd | key = <nowiki>[^\p{Han}]+</nowiki>}} ([https://regex101.com/r/Nk9GdA/1 demo])</td>
<td></td>
</tr>
<tr>
<td> 以「狐狸」開頭的行 <br /> {{kbd | key = <nowiki>^狐狸.*$</nowiki>}}<ref>[http://www.regular-expressions.info/completelines.html Regex Examples: Matching Whole Lines of Text That Satisfy Certain Requirements]</ref></td>
<td>
<span style="background:#C6E3FF">狐狸怎叫 34 What Does the Fox Say?</span><br />
柴犬怎叫 What Does the shiba inu say?
</td>
<td>不以「狐狸」開頭的行   <br /> {{kbd | key = <nowiki>^(?!狐狸).*$</nowiki>}}<ref>[http://stackoverflow.com/questions/406230/regular-expression-to-match-text-that-doesnt-contain-a-word regex - Regular expression to match text that *doesn't* contain a word? - Stack Overflow]</ref> </td>
<td>
狐狸怎叫 34 What Does the Fox Say?<br />
<span style="background:#C6E3FF">柴犬怎叫 What Does the shiba inu say?</span>
</td>
</tr>
<tr>
<td> 以「怎叫」結尾的行 <br /> {{kbd | key = <nowiki>^.*怎叫$</nowiki>}}
<td>
What Does the Fox Say? 12 狐狸怎叫 34<br />
<span style="background:#C6E3FF">What Does the shiba inu say? 柴犬怎叫</span>
</td>
<td>不以「怎叫」結尾的行   <br /> {{kbd | key = <nowiki>.*(?<!怎叫)$</nowiki>}}<ref>[http://stackoverflow.com/questions/16398471/regex-not-ending-with Regex not ending with - Stack Overflow]</ref></td>
<td>
<span style="background:#C6E3FF">What Does the Fox Say? 12 狐狸怎叫 34</span><br />
What Does the shiba inu say? 柴犬怎叫
</td>
</tr>
<tr>
<td> 包含「狐狸」的行 <br /> {{kbd | key = <nowiki>^.*狐狸.*$</nowiki>}} 或 {{kbd | key = <nowiki>(狐狸)</nowiki>}} ([https://regex101.com/r/UEtYst/1 demo])</td>
<td>
<span style="background:#C6E3FF">What Does the Fox Say? 12 狐狸怎叫 34</span><br />
What Does the shiba inu say? 柴犬怎叫
</td>
<td>不包含「狐狸」的行 ([https://regex101.com/r/rvncjU/1 demo]) <br /> {{kbd | key = <nowiki>^((?!狐狸).)*$</nowiki>}} </td>
<td>
What Does the Fox Say? 12 狐狸怎叫 34<br />
<span style="background:#C6E3FF">What Does the shiba inu say? 柴犬怎叫 </span>
</td>
</tr>
<tr>
<td> 布林邏輯 AND: 包含「狐狸」和「叫」的行 ([http://regexr.com/3aokl demo])<ref>[http://stackoverflow.com/questions/469913/regular-expressions-is-there-an-and-operator regex - Regular Expressions: Is there an AND operator? - Stack Overflow]</ref><br /> {{kbd | key = <nowiki>(?=.*狐狸)(?=.*叫).*</nowiki>}} 或 {{kbd | key = <nowiki>狐狸.*叫|叫.*狐狸</nowiki>}}</td>
<td>
<span style="background:#C6E3FF">What Does the Fox Say? 12 狐狸怎叫 34</span><br />
<span style="background:#C6E3FF">What Does the Fox Say? 12 不叫狐狸 34</span><br />
What Does the shiba inu say? 柴犬怎叫
</td>
<td></td>
<td></td>
</tr>
<tr>
<td> 布林邏輯 OR: 包含「狐狸」或「叫」的行 ([https://regexr.com/6cu06 demo])<br /> {{kbd | key = <nowiki>.*(狐狸|叫).*</nowiki>}}</td>
<td>
<span style="background:#C6E3FF">What Does the Fox Say? 12 狐狸怎叫 34<br />
What Does the shiba inu say? 柴犬怎叫</span><br />
What Does the shiba inu say? 柴犬怎了
</td>
<td>布林邏輯: 不包含「狐狸」也不包含「柴犬」的行<br /> {{kbd | key = <nowiki>^((?!狐狸|柴犬).)*$</nowiki>}}</td>
<td>What Does the Fox Say? 12 狐狸怎叫 34<br />
What Does the shiba inu say? 柴犬怎叫<br />
<span style="background:#C6E3FF">What Does the Husky say? 哈士奇怎叫 </span></td>
</tr>
<tr>
<td> 布林邏輯 NOT: 不包含「狐狸」，但包含「柴犬」的行 ([http://regexr.com/3aokr demo])<ref>[http://stackoverflow.com/questions/2953039/regular-expression-for-a-string-containing-one-word-but-not-another regex - Regular expression for a string containing one word but not another - Stack Overflow]</ref><br /> {{kbd | key = <nowiki>^((?!狐狸).)*(柴犬).*$</nowiki>}} = {{kbd | key = <nowiki>^(柴犬).*((?!狐狸).)*$</nowiki>}} = {{kbd | key = <nowiki>(柴犬).*((?!狐狸).)*</nowiki>}} (如果句子同時存在狐狸和柴犬會出錯) </td>
<td>
What Does the Fox Say? 12 狐狸怎叫 34<br />
<span style="background:#C6E3FF">What Does the shiba inu say? 柴犬怎叫</span>
</td>
<td></td>
<td></td>
</tr>
</table>

== Regular expression online tools ==
測試 Regular expression 語法的網站
* {{Gd}} [http://regex101.com/ RegEx101] "Online regex tester and debugger: PHP, PCRE, Python, Golang and JavaScript" ([http://regex101.com/r/tH1eT7/1 example]) 有提供語法解說。教學: [https://www.minwt.com/webdesign-dev/html/20352.html RegEx101正規表示法線上產生器，有沒有選到立馬告訴你|梅問題．教學網]
* {{Gd}} [http://gskinner.com/RegExr/ RegExr]: Learn, Build, & Test RegEx ([http://regexr.com/395t0 example]). 有提供語法解說. 教學: [http://blog.hsdn.net/1426.html RegExr: 功能強大的正規式撰寫協助工具]
* [https://regexper.com/ Regexper]: 圖解方式提供語法解說 e.g. [https://regexper.com/#%5Cd%7B3%7D%28.*%29 \d{3}(.*)]
* [https://jex.im/regulex/ Regulex：JavaScript Regular Expression Visualizer] : 圖解方式提供語法解說 e.g. [https://jex.im/regulex/#!flags=&re=%5E(a%7Cb)*%3F%24 ^(a|b)*?$]
* [http://www.rubular.com/ Rubular]: a Ruby regular expression editor and tester ([http://www.rubular.com/r/UZuUT5pjeh example])
* [http://www.phpliveregex.com/ PHP Live Regex] {{access | date=2014-11-25}}
* [http://www.regextester.com/ Regex Tester and Debugger Online - Javascript, PCRE, PHP] {{access | date=2016-01-07}}
* [http://rocksaying.tw/archives/2670695.html Regular Expression (RegExp) in JavaScript - 石頭閒語] {{access | date=2017-11-14}}

Examples
* {{Gd}} [http://regexlib.com/ Regular Expression Library] 網友提供的 pattern 範例

== cases ==
=== 取代換行符號為逗號 ===
將Email清單，轉成Email軟體可以使用的寄信名單
<pre>
原 
aaa@email.com
bbb@email.com
ccc@email.com

改成
aaa@email.com,bbb@email.com,ccc@email.com
</pre>

==== 方案1: Sublime Text, EmEditor ====
語法適用 [http://www.sublimetext.com/ Sublime Text], [http://www.emeditor.com/ EmEditor]軟體 (以下為 EmEditor 的操作說明)
# Menu: Search -> Replace
# click "Use Regular Expression"
## Find: {{kbd | key = <nowiki>\n</nowiki>}} ([[Return symbol | 換行符號]] 。{{Win}} 作業系統的換行符號是 {{kbd | key = <nowiki>\r\n</nowiki>}}、{{Mac}} 作業系統的換行符號是 {{kbd | key = <nowiki>\n</nowiki>}}，取兩者共有的符號。如果使用 {{Linux}} 作業系統的換行符號是 {{kbd | key = <nowiki>\r</nowiki>}}。 )
## Replace with: {{kbd | key = <nowiki>, </nowiki>}}
# click "Replace all"


<div style="float: left; width: 100%; position: relative; display: block; clear: left;">
<div style="width: 46%;  float: left; margin:0 auto; position: relative; display: block; ">
===== 將每行的文字，移除換行，並且都加上逗號分隔 =====
<pre>
// before
Elmo
Emie
Granny Bird

// after
Elmo, Emie, Granny Bird
</pre>
方法: 使用 [http://www.sublimetext.com/ Sublime Text] 或 [https://zh-tw.emeditor.com/ EmEditor]。
* Find what: {{kbd | key = <nowiki>\n</nowiki>}}
* Replace with: {{kbd | key = <nowiki>, </nowiki>}} 此例是將每行的文字，都加上逗號+空格分隔 (如果要用別的符號分隔，例如頓號分隔，則是 Replace with: {{kbd | key = <nowiki>、</nowiki>}})

</div>


<div style="width: 46%; float: left; margin:0 auto; position: absolute; display: block; left: 54%; top: 0;">

===== 將逗號分隔的文字，還原成逐行顯示，並且移除分隔符號 (,) =====
<pre>
// before
Elmo, Emie, Granny Bird

// after
Elmo
Emie
Granny Bird
</pre>
方法: 使用 [http://www.sublimetext.com/ Sublime Text] 或 [https://zh-tw.emeditor.com/ EmEditor]。{{exclaim}} 輸出結果的每行前面可能會有空白
* Find what: {{kbd | key = <nowiki>([^,]+),</nowiki>}}
* Replace with: {{kbd | key = <nowiki>\1\n</nowiki>}}

</div>
</div>
<div style="clear:both;">&nbsp;</div>

==== 方案2: Notepad++ ====
使用[http://notepad-plus-plus.org/ Notepad++]軟體
# 選單: 尋找 -> 取代
# 搜尋模式: 勾選「增強模式」 (不是勾選「用類型表式」)
## 尋找目標: {{kbd | key = <nowiki>\n</nowiki>}} (換行符號)
## 取代成: {{kbd | key = <nowiki>, </nowiki>}}
# 勾選全部取代

相關資料: [http://sourceforge.net/apps/mediawiki/notepad-plus/index.php?title=Replacing_Newlines How To Replace Line Ends, thus changing the line layout] last visited: 2010-01-27

==== 方案3: Microsoft Word ====
使用Microsoft Word 2002軟體
# 選單: 編輯 -> 取代
# 勾選增強模式
## 尋找目標: {{kbd | key = <nowiki>^p</nowiki>}} (段落標記)
## 取代為: {{kbd | key = <nowiki>, </nowiki>}}
# 勾選全部取代

==== 方案4: Sed command for linux ====

{{kbd | key=<nowiki>sed 's/要被取代的字串/新的字串/g' old.filename > new.filename</nowiki>}}<ref>[http://linux.vbird.org/linux_basic/0330regularex.php#sed_replace 鳥哥的 Linux 私房菜 -- 正規表示法 (regular expression, RE) 與文件格式化處理]</ref>

(1)要被取代的字串: :a;N;$!ba;s/\n 
(2)新的字串: ; 

{{kbd | key=<nowiki>sed ':a;N;$!ba;s/\n/; /g' old.filename > new.filename</nowiki>}} <ref>參考 [http://stackoverflow.com/questions/1251999/sed-how-can-i-replace-a-newline-n unix - sed: How can I replace a newline? ]</ref>

==== 方案5: 使用支援十六進位編輯 (HEX) 的編輯軟體 ====

使用支援十六進位編輯 (HEX) 的編輯軟體，例如: [https://itunes.apple.com/tw/app/ihex-hex-editor/id909566003?mt=12 ‎iHex - Hex Editor] for {{Mac}}
# 選單 Edit -> Find
# Find: {{kbd | key=<nowiki>0A</nowiki>}} 換行符號
# Replace: {{kbd | key=<nowiki>2c 20</nowiki>}} 其中 2c 是逗號， 20 是空白
# 儲存檔案

相關資料

* [https://www.hexdictionary.com/ Hex Dictionary | Convert Hex / Hexadecimal Numbers to Binary and Decimal]

=== Find IP address (IPv4) ===
適用 [http://notepad-plus-plus.org/ Notepad++] 軟體 v.5.9.5
# 選單: 尋找 -> 取代
# 搜尋模式: 勾選「用類型表式」
## 尋找目標: {{kbd | key=<nowiki>\d\d?\d?\.\d\d?\d?\.\d\d?\d?\.\d\d?\d?</nowiki>}}

note: not support {n} syntax

適用 [https://www.sublimetext.com/ Sublime Text] v. 3.2.21
# Find: {{kbd | key=<nowiki>(?:\d{1,3}\.){3}\d{1,3}</nowiki>}}

參考資料: 
* [https://www.regular-expressions.info/ip.html How to Find or Validate an IP Address] {{access | date = 2019-06-05}}
* [http://sourceforge.net/projects/notepad-plus/forums/forum/331754/topic/4780602 SourceForge.net: Notepad++: Regular expression for IP addresses]
* [http://stackoverflow.com/questions/53497/regular-expression-that-matches-valid-ipv6-addresses regex - Regular expression that matches valid IPv6 addresses - Stack Overflow] {{access | date = 2015-08-10}}

=== 移除記事本純文字檔的黑色方塊(UNIX系統的換行符號 LF ) ===
使用notepad++軟體
# 選單: 尋找 -> 取代
# 搜尋模式: 勾選「增強模式」
## 尋找目標: \n\n  (註: 2個LF )
## 取代成: \r\n  (註: CR與LF )

用記事本打開純文字檔時，就不會看到黑色方塊


=== 將每項元素，加上引號框起來 ===
==== 將陣列的每項元素，都加上引號框起來 ====
<pre>
Elmo, Emie, Granny Bird, Herry Monster, 喀喀獸
修改成
'Elmo', 'Emie', 'Granny Bird', 'Herry Monster', '喀喀獸'
</pre>
方法1: 使用 PHP
{{exclaim}} 如果元素包含換行符號，不能用下面方法處理。
<pre>
$users = array('Elmo', 'Emie', 'Granny Bird', 'Herry Monster', '喀喀獸');
//「單引號」相隔每個元素
$result = implode(",", preg_replace('/^(.*?)$/', "'$1'", $users));

//「雙引號」相隔每個元素
$result = implode(",", preg_replace('/^(.*?)$/', "\"$1\"", $users));
echo $result;
</pre>

Thanks, Joshua! More on [http://melikedev.com/2010/02/24/php-wrap-implode-array-elements-in-quotes/ PHP - Wrap Implode Array Elements in Quotes » Me Like Dev]

方法2: 使用 [http://www.sublimetext.com/ Sublime Text] 或 [https://zh-tw.emeditor.com/ EmEditor]
* Find: {{kbd | key = <nowiki>([^\s|,]+)</nowiki>}} 
* 分隔符號
**「單引號」相隔每個元素 Replace with: {{kbd | key = <nowiki>'\1'</nowiki>}} 
**「雙引號」相隔每個元素 Replace with: {{kbd | key = <nowiki>"\1"</nowiki>}}

方法3: 使用 [https://notepad-plus-plus.org/ Notepad++]。啟用搜尋模式的「用類型表式」
* Find: {{kbd | key = <nowiki>([^\s|,]+)</nowiki>}} 
* 分隔符號
**「單引號」相隔每個元素 Replace with: {{kbd | key = <nowiki>'$1'</nowiki>}} 
**「雙引號」相隔每個元素 Replace with: {{kbd | key = <nowiki>"$1"</nowiki>}}


<div style="float: left; width: 100%; position: relative; display: block; clear: left;">
<div style="width: 46%;  float: left; margin:0 auto; position: relative; display: block; ">

==== 將每行的文字，都加上引號框起來，並且移除換行 ====
<pre>
// before
Elmo
Emie
Granny Bird

// after
'Elmo', 'Emie', 'Granny Bird'
</pre>
方法1: 使用 [http://www.sublimetext.com/ Sublime Text] 、[https://notepad-plus-plus.org/downloads/ Notepad++] 或 [https://zh-tw.emeditor.com/ EmEditor]。該方法有處理每行的前面或後面可能有一格或多格空白

如果使用 {{Mac}} 作業系統
* Find what: {{kbd | key = <nowiki>(\S+)(\s?)+$\n</nowiki>}}
* Replace with: {{kbd | key = <nowiki>'\1', </nowiki>}} <br />(如果要使用雙引號框起來，則是 Replace with: {{kbd | key = <nowiki>"\1", </nowiki>}})

如果使用 {{Win}} 作業系統，需要修改換行符號 {{kbd | key = <nowiki>\n</nowiki>}} 為 {{kbd | key = <nowiki>\r\n</nowiki>}}
* Find what: {{kbd | key = <nowiki>(\S+)(\s?)+$\r\n</nowiki>}} on {{Mac}}
* Replace with: {{kbd | key = <nowiki>'\1', </nowiki>}} <br />(如果要使用雙引號框起來，則是 Replace with: {{kbd | key = <nowiki>"\1", </nowiki>}})


方法2: 使用 [http://www.sublimetext.com/ Sublime Text] 或 [https://zh-tw.emeditor.com/ EmEditor] {{exclaim}} 該方法沒有處理每行的後面可能有一格或多格空白
* Find what: {{kbd | key = <nowiki>(.*)$\n</nowiki>}} 或 {{kbd | key = <nowiki>(\S+)$\n</nowiki>}} 或 {{kbd | key = <nowiki>(\S+)\n</nowiki>}}
* Replace with: {{kbd | key = <nowiki>'\1', </nowiki>}}

More details on the page [[Add quotation at the start and end of each line | add quotation at the start and end of each line]].

</div>


<div style="width: 46%; float: left; margin:0 auto; position: absolute; display: block; left: 54%; top: 0;">

==== 將引號框起來的文字，還原成逐行顯示，並且移除分隔符號 (,) ====
<pre>
// before
'Elmo', 'Emie', 'Granny Bird'

// after
Elmo
Emie
Granny Bird
</pre>
方法: 使用 [http://www.sublimetext.com/ Sublime Text] 或 [https://zh-tw.emeditor.com/ EmEditor]。該方法有處理每行的前面或後面可能有一格或多格空白
* Find what: {{kbd | key = <nowiki>'(([^,|^'])+)',?\s?</nowiki>}}
* Replace with: {{kbd | key = <nowiki>\1\n</nowiki>}}

</div>
</div>

<div style="clear:both;">&nbsp;</div>


=== 將試算表欄位值前後，加上雙引號框起來 ===
* [https://errerrors.blogspot.com/2019/03/how-to-enclose-non-empty-cell-with-double-quotes-in-google-spreadsheet.html Google 試算表的文字類型欄位值的前後加上雙引號]

=== Find non-ASCII characters 尋找中文、非英文的文字 ===
==== Find non-ASCII characters in Google sheet ====
適用: Google Drive 試算表的 Regular expression 相關函數，例如: [https://support.google.com/docs/answer/3098292?hl=zh-Hant REGEXMATCH]、[https://support.google.com/docs/answer/3098244?hl=en REGEXEXTRACT]、[https://support.google.com/docs/answer/3098245?hl=zh-Hant RegExReplace] 函數、Notepad++的搜尋
<pre>
[^\x00-\x80]+
</pre>

==== Find non-ASCII characters in LibreOffice ====
適用: [https://zh-tw.libreoffice.org/ LibreOffice] [https://help.libreoffice.org/6.2/en-US/text/scalc/01/func_regex.html REGEX] function<ref>[https://help.libreoffice.org/6.2/en-US/text/shared/01/02100001.html?&DbPAR=WRITER&System=MAC List of Regular Expressions]</ref>、Total commander 的 Multi-Rename tool<ref>取代非英文的文字，但是不包含 . 符號: <nowiki>[^\u0000-\u0080|.]+ </nowiki></ref><ref>[http://stackoverflow.com/questions/150033/regular-expression-to-match-non-english-characters javascript - Regular expression to match non-english characters? - Stack Overflow]</ref>
<pre>
[^\u0000-\u0080]+
</pre>

==== Find Chinese characters in Google sheet ====
範例：如果 A2 包含任一中文字，則欄位值顯示「中文」。如果未包含任何中文字，則欄位值顯示「英文」：
<pre>
=IF(REGEXMATCH(A2, "[\一-\龥]"), "中文", "英文")
</pre>

{{exclaim}} Google 不支援以下語法，會顯示「... 是無效的規則運算式。」錯誤
* {{kbd | key=<nowiki>[\u4e00-\u9fa5]</nowiki>}}
* {{kbd | key=<nowiki>[^\u4e00-\u9fa5]</nowiki>}}
* {{kbd | key=<nowiki>[\p{Script=Hans}]</nowiki>}}
* {{kbd | key=<nowiki>[\p{Han}]</nowiki>}}

==== Find Chinese characters in MySQL ====
尋找 `column_name` 欄位值包含中文字。適用: MySQL<ref>[https://stackoverflow.com/questions/9795137/how-to-detect-rows-with-chinese-characters-in-mysql How to detect rows with chinese characters in MySQL? - Stack Overflow]</ref><ref>[https://stackoverflow.com/questions/401771/how-can-i-find-non-ascii-characters-in-mysql How can I find non-ASCII characters in MySQL? - Stack Overflow]</ref>
<pre>
SELECT `column_name`
FROM `table_name`
WHERE HEX(`column_name`) REGEXP '^(..)*(E[4-9])';
</pre>

說明
* 正則表達式 '^(..)*(E[4-9])' 的含義是尋找從字符串開始處（表示為 ^），每兩個字符（表示為 ..）重複零次或多次（表示為 *），直到找到一個匹配 (E[4-9]) 的序列。
* 透過加入 ^(..)* 使得搜尋條件更加嚴格，它要求 (E[4-9]) 的出現位置必須是在一個合法的 UTF-8 字符邊界上。這意味著它更可能正確匹配開頭為中文字符的字符串，而忽略那些僅在中間或末尾偶然包含 E4 到 E9 序列的非中文字符串。

==== Find non-ASCII characters in MySQL ====
尋找 `column_name` 欄位值不完全是 ASCII 字元
<pre>
SELECT `column_name`
FROM `table_name`
WHERE `column_name` <> CONVERT(`column_name` USING ASCII)
</pre>

==== Find non-ASCII characters in PHP ====
尋找欄位值包含中文字，中文字包含繁體中文與簡體中文，不包含標點符號 (例如 {{kbd | key = <nowiki>,</nowiki>}})、全形標點符號 (例如 {{kbd | key = <nowiki>，</nowiki>}})以及特殊符號，例如 Emoji：{{kbd | key = ⭐}}。
PHP: exact match
<pre>
// approach 1
if (preg_match('/^[\x{4e00}-\x{9fa5}]+$/u', $string)) {
	echo "全部文字都是中文字" . PHP_EOL;
}else{
	echo "部分文字不是中文字" . PHP_EOL;
}

// approach 2
if (preg_match('/^[\p{Han}]+$/u', $string)) {
	echo "全部文字都是中文字" . PHP_EOL;
}else{
	echo "部分文字不是中文字" . PHP_EOL;
}
</pre>

partial match ([http://sandbox.onlinephpfunctions.com/code/d780845d20877c0fd2e693b28ed02a10d250d39e online demo] hosted by [http://sandbox.onlinephpfunctions.com/ PHP Sandbox])
<pre>
// approach 1
$string = '繁體中文-简体中文-English-12345-。，！-.,!-⭐';
$pattern = '/[\p{Han}]+/u';
preg_match_all($pattern, $string, $matches, PREG_OFFSET_CAPTURE);

var_dump($matches);

// approach 2
$string = '繁體中文-简体中文-English-12345-。，！-.,!-⭐';
$pattern = '/[\x{4e00}-\x{9fa5}]+/u';
preg_match_all($pattern, $string, $matches, PREG_OFFSET_CAPTURE);

var_dump($matches);
</pre>

技術問題除錯: 錯誤訊息
<pre>preg_match(): Compilation failed: character value in \x{} or \o{} is too large at offset 8</pre>

解決方式: [http://php.net/manual/en/function.preg-match.php preg_match()] 需要加上 {{kbd | key = u }} 變數<ref>[https://stackoverflow.com/questions/32375531/preg-match-compilation-failed-character-value-in-x-or-o-is-too-large-a php - preg_match(): Compilation failed: character value in \x{} or \o{} is too large at offset 27 on line number 25 - Stack Overflow]</ref>。

==== Find non-ASCII characters in JavaScript ====
* [https://stackoverflow.com/questions/21109011/javascript-unicode-string-chinese-character-but-no-punctuation regex - Javascript unicode string, chinese character but no punctuation - Stack Overflow]

參考資料: 
* [http://blog.csdn.net/tinyletero/article/details/8201465 unicode编码 \u4e00-\u9fa5 匹配所有中文 - CSDN博客]
* [https://stackoverflow.com/questions/38168419/codeigniter-form-validation-for-chinese-words php - CodeIgniter Form Validation for Chinese Words - Stack Overflow]
* [https://zh.wikipedia.org/zh-tw/%E4%B8%AD%E6%97%A5%E9%9F%93%E7%B5%B1%E4%B8%80%E8%A1%A8%E6%84%8F%E6%96%87%E5%AD%97%E5%88%97%E8%A1%A8 中日韓統一表意文字列表 - 維基百科，自由的百科全書]

=== 尋找英文字 ===


==== 尋找 ASCII 字元 in MySQL ====
<pre>
-- 尋找欄位 `my_column` 欄位值是 ASCII 字元

SELECT * 
FROM `my_table` 
WHERE `my_column` LIKE CONVERT(`my_column` USING ASCII)
</pre>

相關文章
* [https://errerrors.blogspot.com/2020/07/search-app-not-apple-in-englishsearching.html 解決英文字的搜尋：搜尋 app 而不是 apple]

參考資料
* [https://stackoverflow.com/questions/401771/how-can-i-find-non-ascii-characters-in-mysql How can I find non-ASCII characters in MySQL? - Stack Overflow]

==== 尋找 ASCII 字元 in PHP ====

Code I:
<pre>
if (preg_match('/[^\x20-\x7f]/', $keyword) === 0) {
    echo "The keyword is ASCII only";
} else {
    echo "The keyword contains non-ASCII characters (like Chinese, Japanese, etc.)";
}
</pre>

Explanation:

* {{kbd | key=<nowiki>/[^\x20-\x7f]/</nowiki>}} 是一個正規表達式:
** {{kbd | key=<nowiki>\x20</nowiki>}} 代表空格字符 (ASCII 32)
** {{kbd | key=<nowiki>\x7f</nowiki>}} 代表 DELETE 字符 (ASCII 127)
** {{kbd | key=<nowiki>[^\x20-\x7f]</nowiki>}} 表示「任何不在 \x20 到 \x7f 範圍內的字符」
這個範圍 {{kbd | key=<nowiki>(\x20-\x7f)</nowiki>}} 基本上涵蓋了所有可印刷的 ASCII 字符；不符合條件，則表示字串中包含非 ASCII 字符 (如中文、日文等)

Code II<ref>[https://www.php.net/manual/en/regexp.reference.character-classes.php PHP: Character classes - Manual]</ref>
<pre>
$pattern = '/^[[:ascii:]]+$/i';
$text = "Hello World"; // ASCII only
if (preg_match($pattern, $text)) {
    echo "純 ASCII 字元";
} else {
    echo "包含非 ASCII 字元";
}

$text = "Hello 世界"; // Contains non-ASCII
if (preg_match($pattern, $text)) {
    echo "純 ASCII 字元";
} else {
    echo "包含非 ASCII 字元";
}
</pre>

Explanation:
* 匹配整個字串（{{kbd | key=<nowiki>^</nowiki>}} 和 {{kbd | key=<nowiki>$</nowiki>}}）
* 需要符合一個或多個 ASCII 字元（{{kbd | key=<nowiki>[[:ascii:]]+</nowiki>}}）
* 不區分大小寫（{{kbd | key=<nowiki>i</nowiki>}} flag）

==== 尋找英文字、數字、破折號（-）或底線（_）字元 in MySQL ====
<pre>
-- 尋找欄位 `my_column` 欄位值是包含英文字、數字、破折號（-）或底線（_）的字串

SELECT * 
FROM `my_table` 
WHERE `my_column` REGEXP '[a-zA-Z0-9\-_]'
</pre>

=== 將每行文字的行頭加上逗號符號 ===
[[Adding characters to document lines]]

=== 知道前面跟後面的文字，但是中間文字忘記了 ===
使用notepad++軟體
# 選單: 尋找 -> 取代
# 搜尋模式: 勾選「用類型表示」
## 尋找目標: {{kbd | key=a(.*)le}} 就可以找到(1)apple (2)apps lesson ... 等a開頭、le結尾的文字，中間可夾雜空白。 {{exclaim}} 中文字串搜尋，建議將文件的編碼改成 UTF-8 編碼


=== 移除空白行 ===
<pre>
# (原) 每行可能間隔一行空白或多行空白
尼歐
崔妮蒂

莫斐斯


史密斯
祭師

# (後) 改成每行逐行緊接著
尼歐
崔妮蒂
莫斐斯
史密斯
祭師
</pre>

移除一行空白或多行空白( 行內可能包含一個或多個空白字元 {{kbd | key= SPACE}} 、定位鍵{{kbd | key= TAB}})
* 使用工具:  適用 Sublime Text 與 EmEditor 軟體，需勾選「使用規則運算式」。{{exclaim}} 以下語法不適用於 Notepad++ 軟體<ref>[http://www.sitepoint.com/forums/showthread.php?448843-Regex-delete-multiple-blank-lines Regex: delete multiple blank lines]</ref>
** 尋找: {{kbd | key=<nowiki>^[\s\t]*$\n</nowiki>}} --> 取代為: 空 (不需要輸入任何字)
* 使用工具: Notepad++ v7.8.7
** Notepad++ 軟體選單: 編輯 -> 行處理 -> 移除空行(包括只有空白字元的行)<ref>[http://stackoverflow.com/questions/3866034/removing-empty-lines-in-notepad regex - Removing empty lines in Notepad++ - Stack Overflow]</ref>
* 詳細說明，請見 [[Regular replace blank lines]]

=== 尋找非空白的文字 ===
* 尋找: {{kbd | key=<nowiki>[^\s]+</nowiki>}} [https://regex101.com/r/zH7wV3/1 online demo]
* [https://errerrors.blogspot.com/2022/01/avoid-whitespace-character-caused-program-stop-abnormally.html 解決遇到空白段落發生程式異常錯誤而執行中斷的問題] 「... 看起來空白的字元，卻無法使用 TRIM 函數去除，可能是其他的空白字元。解決方式是偵測段落內有沒有包含中英文、數字，再進行後續處理。」

=== 去除標點符號、特殊符號等 ===

* [https://stackoverflow.com/questions/5689918/php-strip-punctuation/5689989 regex - PHP strip punctuation - Stack Overflow]

=== 將特定符號相隔的文字，改成逐行顯示 ===
例子: 
<pre>
# (原) 頓號(、)符號相隔的文字
尼歐、莫斐斯、崔妮蒂、史密斯、祭師

# (後) 改成逐行顯示
尼歐
莫斐斯
崔妮蒂
史密斯
祭師
</pre>

使用 [http://www.sublimetext.com/ Sublime Text] 或 [https://zh-tw.emeditor.com/ EmEditor]
* Find: {{kbd | key = <nowiki>([^、]+)([、]{1})</nowiki>}} 
* Replace with: {{kbd | key = <nowiki>\1\n</nowiki>}}

語法說明
* <nowiki>[^、]</nowiki> : 符合任意字，但不是頓號(、)的文字
* <nowiki>[^、]+</nowiki> : 一次以上不是頓號(、)的文字
* <nowiki>([^、]+)</nowiki> : 符合「一次以上不是頓號(、)的文字」規則的文字
* <nowiki>[、]</nowiki>: 出現頓號(、)任意次的文字
* <nowiki>[、]{1}</nowiki> : 出現頓號(、)一次的文字
* <nowiki>([、]{1})</nowiki> : 符合「出現頓號(、)一次的文字」規則的文字

=== 將每行文字的結尾處，加入空一格 (半形空白) ===
法1: 適用軟體: Sublime Text, EmEditor
# Menu: Search -> Replace
# click "Use Regular Expression"
## Find: {{kbd | key = <nowiki>\n</nowiki>}} 
## Replace with: {{kbd | key = <nowiki>_\n</nowiki>}}(符號 {{kbd | key = <nowiki>\n</nowiki>}} 前面的 _ 自行替換成半形空白)
# click "Replace all"


法2: 適用軟體: Sublime Text, EmEditor
# Menu: Search -> Replace
# click "Use Regular Expression"
## Find: {{kbd | key = <nowiki>$</nowiki>}} 
## Replace with: {{kbd | key = <nowiki>_$</nowiki>}}(符號 {{kbd | key = <nowiki>$</nowiki>}} 前面的 _ 自行替換成半形空白)
# click "Replace all"


{{exclaim}} 需要檢查最後一行是否是空白行，如果不是空白行，不會套用到該取代規則

=== 將每行文字內夾雜的空白，取代成 Tab 符號 ===
將原本空白間隔的欄位值，取代成 Tab鍵間隔的欄位值。輸出結果可以方便貼到 MS Excel 或 [[Google spreadsheet]]。 
<pre># \t 代表是 Tab 鍵，又稱定位鍵
# before
aaa bbb    ccc

# after
aaa\tbbb\tccc
</pre>

說明: \S 代表非空白字元, \r\n 代表[[Return symbol | 換行符號]]。[^\S\r\n] 則代表不是非空白字元、也不是換行符號。換句話說尋找空白，但不包含換行符號。

使用  Sublime Text 軟體 (參考資料<ref>[http://www.techrepublic.com/blog/microsoft-office/quickly-replace-multiple-space-characters-with-a-tab-character/ Quickly replace multiple space characters with a tab character - TechRepublic]</ref> <ref>[http://stackoverflow.com/questions/3469080/match-whitespace-but-not-newlines-perl regex - Match whitespace but not newlines (Perl) - Stack Overflow]</ref>)
# Menu: Search -> Replace
# click "Use Regular Expression"
## Find: {{kbd | key = <nowiki>([^\S\n]+)</nowiki>}} 或 {{kbd | key = <nowiki>([^\S\r\n]+)</nowiki>}} 或 {{kbd | key = <nowiki>\s\s+</nowiki>}} 或 {{kbd | key = <nowiki>_{1,}</nowiki>}} ( 自行替換 _ 成半形空白) {{exclaim}} 因為 {{kbd | key = <nowiki>\s</nowiki>}} 包含了空白與換行字元，所以不能直接使用 {{kbd | key = <nowiki>\s+</nowiki>}} 當做搜尋條件
## Replace with: {{kbd | key = <nowiki>\t</nowiki>}}
# click "Replace all"

=== 移除每行文字前後面可能多個的空白 ===
==== 移除每行文字最前面可能多個的空白 ====
* 尋找: {{kbd | key = <nowiki>^\s+</nowiki>}} --> 取代為: 空白 (適用軟體: Sublime Text、EmEditor，需啟用 "Use Regular Expression" )

<pre># before
aaa 
 bbb
    ccc

# after
aaa 
bbb
ccc
</pre>


==== 移除每行文字最後面可能多個的空白 ====
* 尋找: {{kbd | key = <nowiki>\s+$</nowiki>}} --> 取代為: 空白 (適用軟體: Sublime Text、EmEditor，需啟用 "Use Regular Expression" )


==== 移除每行文字前面或後面可能多個的空白 ====
* 尋找: {{kbd | key = <nowiki>(^\s+|\s+$)</nowiki>}} --> 取代為: 空白 (適用軟體: Sublime Text、EmEditor，需啟用 "Use Regular Expression" )

=== 尋找包含不是數字，是文字的行 ===
預期每行資料都是數字，尋找包含不是數字，是文字的行
<pre>
[^\d|\n]
</pre>

=== 尋找 Hashtag ===
[[Extract all hashtags from text]]

=== 尋找文章內容中的網址 ===
[[Extract url from text]]


=== 尋找數字 ===
請參考 [[Data cleaning#Numeric]]

* [[Extract large number from text | 尋找文章內容中的長數字]]
* [https://errerrors.blogspot.com/2020/02/convert-minguo-calendar-to-common-era-using-google-sheet.html Google 試算表將民國轉西元日期]

=== 移除刮號內的文字 ===
請參考 [[Remove text within brackets]]

=== Search unmatched string ===
find un-commented console.log:

original format: some lines contains un-commented [[Javascript debug]] information
<pre>
   console.log("un-commented debug information");

  //console.log("commented debug information");
</pre>

Search pattern: find not started with the / symbol before the string "console.log"

<pre>
   [^/](console\.log)
</pre>

== Text editor with support for regular expression ==
[[Text editor with support for regular expression]]

== Regular expression batch tools ==
'''multiple''' regular expression operations on the same file
* {{Gd}} [https://github.com/facelessuser/RegReplace RegReplace] 執行多個取代命令 "Simple find and replace sequencer plugin for Sublime Text" Quoted from official webpage. {{access | date=2014-10-25}}
* ''$'' [https://www.emeditor.com/text-editor-features/more-features/batch-replace/ EmEditor (Text Editor) - Batch Replace] & [https://zh-tw.emeditor.com/text-editor-features/coding/regular-expressions/ EmEditor (文字編輯器) | 規則運算式]

one regular expression operations on '''multiple''' files
* ''$''  [https://www.emeditor.com/text-editor-features/more-features/find-replace/ EmEditor (Text Editor) | Find and Replace]

== syntax ==
* 換行符號: \r\n (適用: Notepad++選項: 增強模式 & 用類型表式)
* tab鍵的固定空白分隔: \t  (適用: Notepad++選項: 增強模式)
* 數字: \d (適用: Notepad++選項: 用類型表式。{{exclaim}} 不適用: Notepad++選項: 增強模式)
* {{kbd | key=<nowiki>\S</nowiki>}} 非空白的文字: 不會含括半形空白與全行空白

== Troubleshooting of regular expression ==
Tips
* Use online tool [https://regex101.com/ regex101: build, test, and debug regex] to obtain the explain of your syntax
* Small data test: (1) Prepare the small file data to verify the syntax (2) Using the [[Regular_expression#Regular_expression_online_tools | online tools]]
* Highlight or output the matched text e.g. {{kbd | key=<nowiki>--color</nowiki>}}<ref>[https://www.cyberciti.biz/faq/howto-use-grep-command-in-linux-unix/grep_command_examples/ Grep -color command Examples - nixCraft]</ref> for grep command or output the matches by PHP [http://php.net/manual/en/function.preg-match.php preg_match()] function.
* Simplify the syntax
* Because the compatibility issue, you may try to use the alternative syntax e.g. {{kbd | key=<nowiki>\d</nowiki>}} to {{kbd | key=<nowiki>[0-9]+</nowiki>}}.

Related articles
* [https://errerrors.blogspot.com/2015/07/sublime-text-invalid-lookbehind.html Err: 解決 Sublime Text 正則表示式搜尋，遇到的「Invalid lookbehind assertion」錯誤]

== further reading ==
* [http://sourceforge.net/apps/mediawiki/notepad-plus/index.php?title=Searching_And_Replacing SourceForge.net: Searching And Replacing - notepad-plus], [http://sourceforge.net/apps/mediawiki/notepad-plus/index.php?title=Regular_Expressions SourceForge.net: Regular Expressions - notepad-plus]
* [http://stackoverflow.com/questions/23020856/text-extraction-with-sublime-text regex - text extraction with sublime text - Stack Overflow] {{access | date=2014-09-26}}
* [https://zh.wikipedia.org/wiki/%E6%AD%A3%E5%88%99%E8%A1%A8%E8%BE%BE%E5%BC%8F 正規表示式 - 維基百科，自由的百科全書]
* [http://www.regular-expressions.info/ Regular-Expressions.info - Regex Tutorial, Examples and Reference - Regexp Patterns]
* [http://linux.vbird.org/linux_basic/0320bash.php 鳥哥的 Linux 私房菜 -- 第十章、認識與學習BASH] {{access | date = 2016-06-08}}
* [https://stackoverflow.com/questions/3548453/negative-matching-using-grep-match-lines-that-do-not-contain-foo Negative matching using grep (match lines that do not contain foo) - Stack Overflow] {{access | date = 2018-04-06}}
* [https://support.google.com/a/answer/1371415?hl=zh-Hant 規則運算式的語法 - G Suite 管理員說明] {{access | date = 2018-12-06}}
unicode
* [http://www.regular-expressions.info/unicode.html Regex Tutorial - Unicode Characters and Properties] {{access | date = 2014-04-02}}
* [http://php.net/manual/en/regexp.reference.unicode.php PHP: Unicode character properties - Manual] {{access | date = 2014-04-02}}

references
<references/>

== 替代方案 ==
* 將資料以 {{kbd |key=Tab}}來隔開，貼到Google Drive的Spreadsheet或MS Excel，會自動儲存到不同欄位。所以將需要處理的原始資料中，需要擷取的資料的前後，使用{{kbd |key=Tab}}來隔開，複製後貼到於Google Drive的Spreadsheet或MS Excel，就會自動儲存到不同欄位，方便做進一步處理。

Copy multiple rows & paste
* Copy to dreamweaver from MS Excel 2002: ok
* Copy to dreamweaver from Google Docs: not ok {{exclaim}}
* Copy to MS Excel 2002 from Google Docs: ok


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