I am writing an web application. I am getting information as string at UI level using server API . Such response from server side is single string. Structure of these strings is following:
Response ({numberParam} points)
It is always constant. Examples of getting strings:
Response (76 points)
Response (5193 points)
Response (4 points)
Response (21 points)
I need retrieve only value of this numeric parameter from getting string.
I should not use any external libraries and frameworks. Only native JavaScript.
I will be grateful for any advice!
I would use regular expressions, which are perfect for matching patterns like this. Here is a regular expression used to split the input string into parts split by one or more non-digit characters (\D+) so that the resultant array looks like ['','76',''], and you can select position 1 ([1]) from that array.
var str = "Response (76 points)"
var num = str.split(/\D+/)[1]
console.log(num)
Alternatively, you could replace all non numeric characters with nothing...
var num = str.replace(/\D/g,'')
console.log(num)
Or match the first chain of numeric characters...
var num = str.match(/\d+/)[0]
console.log(num)
Or possibly the most useful, is to split by one or more non-word characters (\W+) which gives an array of words, and then select the part you want. I like this, as it is able to retrieve other meaningful information from error messages, and can be applied to many different error messages and situations...
var parts = str.split(/\W+/)
// parts is: [ 'Response', '76', 'points', '' ]
var num = parts[1]
console.log(num)