Javascript Regexp 从变量动态生成？
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Javascript Regexp dynamic generation from variables?
提问by Somebody
How to construct two regex patterns into one?
如何将两个正则表达式模式构建为一个？
For example I have one long pattern and one smaller, I need to put smaller one in front of long one.
例如我有一个长图案和一个较小的图案，我需要将较小的图案放在长图案的前面。
var pattern1 = ':\(|:=\(|:-\(';
var pattern2 = ':\(|:=\(|:-\(|:\(|:=\(|:-\('
str.match('/'+pattern1+'|'+pattern2+'/gi');
This doesn't work. When I'm concatenating strings, all slashes are gone.
这不起作用。当我连接字符串时，所有斜线都消失了。
回答by Felix Kling
You have to use RegExp:
你必须使用RegExp：
str.match(new RegExp(pattern1+'|'+pattern2, 'gi'));
When I'm concatenating strings, all slashes are gone.
当我连接字符串时，所有斜线都消失了。
If you have a backslash in your pattern to escape a special regex character, (like \(), you have to use twobackslashes in the string (because \is the escape character in a string): new RegExp('\\(')would be the same as /\(/.
如果您的模式中有一个反斜杠来转义特殊的正则表达式字符（如\(），则必须在字符串中使用两个反斜杠（因为\是字符串中的转义字符）：new RegExp('\\(')将与/\(/.
So your patterns have to become:
所以你的模式必须变成：
var pattern1 = ':\(|:=\(|:-\(';
var pattern2 = ':\(|:=\(|:-\(|:\(|:=\(|:-\(';
回答by adarshr
Use the below:
使用以下：
var regEx = new RegExp(pattern1+'|'+pattern2, 'gi');
str.match(regEx);
回答by alex
You have to forgo the regex literal and use the object constructor, where you can pass the regex as a string.
您必须放弃正则表达式文字并使用对象构造函数，您可以在其中将正则表达式作为字符串传递。
var regex = new RegExp(pattern1+'|'+pattern2, 'gi');
str.match(regex);
回答by Vinoth Narayan
The RegExp constructor creates a regular expression object for matching text with a pattern.
RegExp 构造函数创建一个正则表达式对象，用于将文本与模式匹配。
var pattern1 = ':\(|:=\(|:-\(';
var pattern2 = ':\(|:=\(|:-\(|:\(|:=\(|:-\(';
var regex = new RegExp(pattern1 + '|' + pattern2, 'gi');
str.match(regex);
Above code works perfectly for me...
上面的代码非常适合我......
