RegExp，只允许在单词:间留空格
it1352
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问题说明
我正在尝试编写一个正则表达式来从单词的开头删除空格，而不是在单词后面的单个空格中删除空格。
I'm trying to write a regular expression to remove white spaces from just the beginning of the word, not after, and only a single space after the word.
使用RegExp：
var re = new RegExp(/^([a-zA-Z0-9] \s?)*$/);
测试Exapmle：
1) wordX[space] - Should be allowed
2) [space] - Should not be allowed
3) WrodX[space][space]wordX - Should be allowed
4) WrodX[space][space][space]wordX - Should be allowed
5) WrodX[space][space][space][space] - Should be not be allowed
6) WrodX[space][space] - Allowed with only one space the moment another space is entered **should not be allowed**
正确答案
#1
试试这个：
^\s*\w (\s?$|\s{2,}\w )
测试用例（为了清晰起见，添加了）：
Test cases ("s added for clarity):
"word" - allowed (match==true)
"word " - allowed (match==true)
"word word" - allowed (match==true)
"word word" - allowed (match==true)
" " - not allowed (match==false)
"word " - not allowed (match==false)
"word " - not allowed (match==false)
" word" - allowed (match==true)
" word" - allowed (match==true)
" word " - allowed (match==true)
" word word" - allowed (match==true)
这篇好文章是转载于：学新通技术网
