如何使用“＆”或“？”进行正则表达式调用？ 作为第一个角色

Question

I am trying to make a regex call with the following string:

if ((/&timeout=true|?scn=header/i).test(url))

... and the statement continues. I am receiving this error in the console:

Uncaught SyntaxError: Invalid regular expression: /&timeout=true|?scn=header/ : Nothing to repeat

How do I properly make this statement?

Answer 1

您必须转义问号字符，因为它是正则表达式运算符：

if ((/&timeout=true|\?scn=header/i).test(url))

Answer 2

The problem is that ? has a special meaning of repeat zero or one times , hence the error. Just escape it:

/&timeout=true|\?scn=header/

Answer 3

Try /(&timeout=true|\\?scn=header)/i

? is a special character in regex so you need to escape it

Answer 4

Demo: http://www.regexr.com/3bqlu

Try this:

/[&\\?]timeout=true|[&\\?]scn=header/

It matches both

http://example.com/file.html?scn=header&timeout=true
http://example.com/file.html?timeout=true&scn=header

because we don't know which parameter comes first

Answer 5

这似乎有效

/\\&timeout=true|\\/?scn=header/i