正则表达式匹配第一个和最后一个字符 [英] Regular Expression to match first and last character

问题描述

我知道这是匹配第一个字符：

  / ^ [az] / i 
  

但是如何才能检查最后一个字符？这是：

  / ^ [az] [az] $ / i 
  pre> 
 
 
不工作。我怀疑两个条款之间应该有什么，但我不知道什么！
 
 
 
任何帮助将不胜感激。
解决方案
下面的正则表达式将匹配以alpha字符开头和结尾的字符串。
  / ^ [az]。* [az] $ / igm 
  
  a 字符串也以字母开头和结尾，对吧？那么你必须使用下面的正则表达式。
  / ^ [az]（。* [az]）？$ / igm 
  
 演示 
 
 
 
 说明： 
 code> ^＃表示开始一行。 
 [a-z]＃alphabatic character。 
。*＃任意字符0次以上。 
 [a-z]＃alphabatic character。 
 $＃一行结束。 
我＃不区分大小写的匹配。 
 g＃global。 
 m＃multiline 
  
 
I'm trying to use regex to check that the first and last characters in a string are alpha characters between a-z.

I know this matches the first character:
/^[a-z]/i
but how do I then check for the last character as well? This:
/^[a-z][a-z]$/i
does not work. And I suspect there should be something in between the two clauses but I don't know what!

Any help would be much appreciated.
解决方案
The below regex will match the strings that starts and ends with alpha character.
/^[a-z].*[a-z]$/igm
a string also starts and endswith alpha character , right? Then you have to use the below regex.
/^[a-z](.*[a-z])?$/igm
DEMO

Explanation:
^             #  Represents  begining of a line.
[a-z]         #  alphabatic  character.
.*            #  Any character 0 or more times.
[a-z]         #  alphabatic  character.
$             #  End of a line.
i             #  case-insensitive match.
g             #  global.
m             #  multiline


                        
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