Javascript regex to extract variables

Question

I have a string in Javascript that contains variables with the format ${var-name} . For example:

'This is a string with ${var1} and ${var2}'

I need to get these variables in an array: ['var1','var2'] .

Is this possible with regex?

Answer 1

Have a try with:

/\$\{(\w+?)\}/

Running example, many thanks to @RGraham :

var regex = new RegExp(/\$\{(\w+?)\}/g),
    text = "This is a string with ${var1} and ${var2} and {var3}",
    result,
    out = [];
while(result = regex.exec(text)) {
    out.push(result[1]);
}
console.log(out);

Answer 2

This regex - \\${([^\\s}]+)(?=}) - should work.

Explanation:

• \\${ - Match literal ${
• ([^\\s}]+) - A capture group that will match 1 or more character that are not whitespace or literal } .
• (?=}) - A positive look-ahead that will check if we finally matched a literal } .

Here is sample code:

 var re = /\\${([^\\s}]+)(?=})/g; var str = 'This is a string with ${var1} and ${var2} and {var3}'; var arr = []; while ((m = re.exec(str)) !== null) { arr.push(m[1]); } alert(arr); 

Answer 3

var str = 'This is a string with ${var1} and ${var2}';

var re = /\$\{(\w+?)\}/g;
var arr = [];
var match;
while (match = re.exec(str)) {
  arr.push(match[1]);
}

console.log(arr);