How to get word that is after indexOf(“@”) and add it to array

by

as the manual states indexOf takes a second parameter, instructing the function to search starting from specific position. So when you want to extract the word after the @ sign you are lookign for the portion of text between @ and the next space eg

hello @valerj how are you
      ^      ^
      p1     p2

so you would use 

p1   = str.indexOf('@');
p2   = str.indexOf(' ',p1);
name = str.substr(p1,p2-p1); //substr want start and length

yet as you see it would fail on a lot of strings like

hello @valerij, how are you
ping @valerij
             ^line end

you could adress this issue by using regex to obtain the p2 eg

p2   = str.indexOf(/ ,.?!$/,p1);

but it might still fail. The best solution would be to use regex for all the operation eg

var myregexp = /@(\w+)\b/;

(the \b is word boundary and will take care of all punctuation, line endings and other characters)
and use this code

var userNames = [];
var match = myregexp.exec(str);
while (match != null) {
    //username is in match[1] (first capturing group)
    userNames.push(match[1]);
    match = myregexp.exec(subject);
}

to populate the array with usernames mentioned in the chat message

More Related Contents:

  1. The color of an echo
  2. Get escaped URL parameter
  3. Run JavaScript code on window close or page refresh?
  4. Passing variables to the next middleware using next() in Express.js
  5. d3 add text to circle
  6. Open page in new window without popup blocking
  7. NavigationDuplicated Navigating to current location (“/search”) is not allowed
  8. Save images to hard disk WITHOUT prompt?
  9. What’s the difference between “{}” and “[]” while declaring a JavaScript array?
  10. Prevent Address-Bar hiding in mobile Browsers
  11. rotate a .gif image on google maps api v3?
  12. How to change FontSize By JavaScript?
  13. How can I get jQuery .val() AFTER keypress event?
  14. How to find the sum of all numbers between 1 and N using JavaScript
  15. What do “>>” and “
  16. How to change mock implementation on a per single test basis?
  17. Bootstrap modal: background jumps to top on toggle
  18. How to define the css :hover state in a jQuery selector?
  19. Javascript multiple dynamic addEventListener created in for loop – passing parameters not working
  20. Is there any way to get current time in nanoseconds using JavaScript?
  21. Why is it suggested to avoid .innerHTML?
  22. Override styles in a shadow-root element
  23. Work with a time span in Javascript
  24. Chrome debugging – break on next click event
  25. What are differences between SystemJS and Webpack?
  26. Server cleanup after a client disconnects
  27. WebSocket on IE10 giving a SecurityError
  28. simplest cross-browser check if protocol handler is registered
  29. JavaScript Namespace Declaration
  30. Use a web mobile framework?

Leave a Comment