简单的JavaScript字符串提取

Question

I have such string:

"{{foo}} is {{bar}}"

I would like to extract values from {{}}, how I can achieve this? Expected result is

["foo", "bar"]

I tried

"{{foo}} is {{bar}}".match(/\{\{(.*?)\}\}/g)

But its not working as I expected.

Answer 1

You should use exec in a loop like this to grab capturing groups with global flag in JS:

var m;
var re = /\{\{(.*?)\}\}/g
var str = "{{foo}} is {{bar}}"
var matches = [];

while((m=re.exec(str)) != null) {
   matches.push(m[1]);
}

console.log(matches);
//=> ["foo", "bar"]

Answer 2

Regex is fine, just use map to strip the braces

  var output = "{{foo}} is {{bar}}".match(/\\{\\{(.*?)\\}\\}/g).map(function(value){ return value.substring(2,value.length-2) }); document.body.innerHTML += output; 

Answer 3

In JS, match with g only returns top-level matches, no groups. You can map the string as @gurvinder372 suggested:

 res = "{{foo}} is {{bar}}".match(/{{.*?}}/g).map(s => s.slice(2, -2)); document.write('<pre>'+JSON.stringify(res,0,3)); 

or use .replace to populate the array:

 res = []; "{{foo}} is {{bar}}".replace(/{{(.*?)}}/g, (_, $1) => res.push($1)); document.write('<pre>'+JSON.stringify(res,0,3)); 

Note that there's no need to escape curly braces in your regex.

Answer 4

Try this

 var arr = []; var str = "{{foo}} is {{bar}}" str.replace(/{{(.*?)}}/g, function(s, match) { arr.push(match); }); document.write('<pre>'+JSON.stringify(arr));