if charAt equal to a list of characters

javascript charat
lbutlr picture lbutlr · Jan 27, 2014 · Viewed 7.2k times · Source

I want something like the following in Javascript

if str.charAt(index) (is in the set of) {".", ",", "#", "$", ";", ":"}

Yes, I know this must be simple, but I can't seem to get the syntax right. What I have now is

theChar = str.charAt(i);
if ((theChar === '.') || (theChar === ',') || (theChar === ... )) {
  // do stuff
}

This works, but there must be a better way.

Edit: I did this, but not sure if it's GOOD or not:

var punc = {
    ".":true,
    ",":true,
    ";":true,
    ":":true
};

if (punc[str.charAt[index]) { ...

Answer

user1620696 picture user1620696 · Jan 27, 2014

Define an array with those chars and simply search in the array. One way to do that is the following:

var charsToSearch = [".", ",", "#", "$", ";", ":"];
var theChar = str.charAt(i); /* Wherever str and i comes from */

if (charsToSearch.indexOf(theChar) != -1) {
    /* Code here, the char has been found. */
}

Related questions

loop over array using charAt to get first letter of each value in javascript

I am new to JS and am trying to understand chartAt. I created a problem where I want to go through an array and pull the first character of each value from my array using charAt. I'm a bit stuck …

Read More
traverse a string char by char javascript

function SimpleSymbols(str) { var letter =['a','b','c','d','e','f','g','h','i','j', 'k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']; var newstr = ""; for (var i = 0; i<str.length; …

Read More
Title Case JavaScript

I am trying to create a function in which after toLowerCase() input, will then capitalize the first letter in each element of an array. function title_case ( String ) { var result = ""; var text = String.toLowerCase().split(" "); for (var i = 0; i < …

Read More