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regexregular-language

How to write a RegExp to match the Nth character

There is a strings as below:

2016,07,20,19,20,25

How can I transfer this strings to such as this format string:

2016-07-20 19:20:25

Thank you very much!

Solution

  • A solution with array slice could be this

    let parts = [];
let date = "2016,07,20,19,20,25"; 
let formatted = ((parts = date.split(",")).slice(0,3)).join("-") + ' ' + parts.slice(3).join(":")

    You could also do it with String#replace and a function as the 2 argument;

    let date = "2016,07,20,19,20,25"; 
date.replace(/,/g, (() => {
  let count = 0;
  return (match, position) => {
    count += 1;
    if(count == 3) return ' ';
    else if(count < 3) return '-';
    else return ':';        
  });
})())

    Note: Both approaches assume that the format will always be the one provided 6 numbers seperated by commas