Regular Expression substring start and end with JavaScript

Question

I have a string:

"/upload/c_fill,w_960,h_640/v1430399111/"

Where i want to replace wherever "w_" to some other value, say w_960 to w_930 while 960 could be vary.

i tried following but not able to find string end with:

var imgPath = elemPath.replace(/(\,w_)/, ",w_"+930);

Answer 1

If I understand you correctly you wanted to replace ,w_ followed by three digits with ,w_930 . You were on the right track. You can use \\d to match a digit and {3} for three repetitions. Also you don't need the group () or to escape the comma:

var imgPath = elemPath.replace(/,w_\d{3}/, ",w_"+930);

If the number of digits can vary, use + (one or more repetitions):

var imgPath = elemPath.replace(/,w_\d+/, ",w_"+930);