Question

我想编写一个正则表达式来匹配单引号中的字符串，但不应该匹配带双引号的单引号的字符串。

示例1：

a = 'This is a single-quoted string';

a 的整个值应该匹配，因为它用单引号括起来。

编辑：完全匹配应该是： ＆＃39;这是一个单引号字符串＆＃39;

示例2：

x = "This is a 'String' with single quote";

x 不应返回任何匹配项，因为单引号位于双引号内。

我尝试了 /＆＃39;。*＆＃39; / g ，但它也匹配双引号字符串中的单引号字符串。

感谢您的帮助！

编辑：

使其更清晰

鉴于以下字符串：

The "quick 'brown' fox" jumps
over 'the lazy dog' near
"the 'riverbank'".

匹配应该只是：

'the lazy dog'

Answer 1

假设不必处理转义引号（这可能会使正则表达式复杂化），并且所有引号都是正确平衡的（不像It's... "Monty Python's Flying Circus"!），那么你可以寻找单引号引用的字符串后跟偶数个双引号：

/'[^'"]*'(?=(?:[^"]*"[^"]*")*[^"]*$)/g

见live on regex101.com。

<强>解释

'        # Match a '
[^'"]*   # Match any number of characters except ' or "
'        # Match a '
(?=      # Assert that the following regex could match here:
 (?:     # Start of non-capturing group:
  [^"]*" # Any number of non-double quotes, then a quote.
  [^"]*" # The same thing again, ensuring an even number of quotes.
 )*      # Match this group any number of times, including zero.
 [^"]*   # Then match any number of characters except "
 $       # until the end of the string.
)        # (End of lookahead assertion)

Answer 2

尝试这样的事情：

^[^"]*?('[^"]+?')[^"]*$

Live Demo

Answer 3

如果你没有严格限制正则表达式，你可以使用函数＆＃34; indexOf＆＃34;找出它是否是双引号匹配的子串：

var a = "'This is a single-quoted string'";
var x = "\"This is a 'String' with single quote\"";

singlequoteonly(x);

function singlequoteonly(line){
    var single, double = "";
    if ( line.match(/\'(.+)\'/) != null ){
        single = line.match(/\'(.+)\'/)[1];
    }
    if( line.match(/\"(.+)\"/) != null ){
        double = line.match(/\"(.+)\"/)[1];
    }

    if( double.indexOf(single) == -1 ){
        alert(single + " is safe");
    }else{
        alert("Warning: Match [ " + single + " ] is in Line: [ " + double + " ]");
    }
}

请参阅下面的JSFiddle：

JSFiddle

RegEx：匹配用单引号括起来的字符串，但不匹配双引号内的字符串

3 个答案:

Live Demo