Javascript模式不匹配

Question

I am trying to match pattern which contains pipe(|) operator.

Have used below code to match patteren

var format = /[ \\|]/; // This is the pattern for matching pipe pattern

if ("Near raghavendra temple ring roads".match(format)) {
    alert("Invalid character");
} 

"Near raghavendra temple ring roads" this string does not contains | operator but still above condition getting true.

Not able to to understand what is the mistake in above pattern.

Answer 1

 var format = /[\\\\|]/; // This is the pattern for matching pipe pattern if ("Near raghavendra temple ring roads".match(format)) console.log("Invalid character"); else console.log('All valid'); 

You are matching on the space character. Remove the space from the regex pattern (inside the square) brackets

Answer 2

The problem is you have a space in there:

/[ \\|]/

actually means "match any one space, \\ or | ".

If all you want to do is match a pipe, then use this:

 const format = /[\\|]/; // This is the pattern for matching pipe pattern if ("Near raghavendra temple ring roads".match(format)) { console.log("Invalid character"); } else { console.log("Okay"); } 

You probably have the double- \\ because that's how it needs to appear in strings. However, in regex, if you do two, it makes it a \\ literal. If you just want to escape the pipe, just use one.

In fact, in a set like that, you don't even need to escape it:

 const format = /[|]/; // This is the pattern for matching pipe pattern if ("Near raghavendra temple ring roads".match(format)) { console.log("Invalid character"); } else { console.log("Okay"); } if ("Bad | character".match(format)) { console.log('Bad character'); } 

Personally, I like to keep the slash though just for clarity.