Test If Input Values Match Constant Value

Ive got an assignment and am a bit stuck. Need to match an input string to the values in a constant, but I am matching individual characters. My constant would be ALPHABET = 'ABCDE

Solution 1:

Here's a single line answer to your question:

(ALPHABET.match(new RegExp((input.split('').join('|')), 'g'))).length == input.length

which would return true only if all the characters in input are present in ALPHABET

Here's a working demo http://jsfiddle.net/kayen/akL4A/

Solution 2:

One way is to loop over the input and search if it exits in the constant

Possible code

var ALPHABET = 'ABCDEFGHIJKLMNOPQRSTUWXYZ';
var input = 'ABOZ'var count = 0;  
    for(x in input) {
        if(ALPHABET.indexOf(input[x])>-1){
            count++;
            continue;
        }
        else{
            break;
        }

    }
if(count==input.length) {
    alert("true");       
}

Demo

Solution 3:

Tested and works in Firefox 16. Remember this implementation does not verify if input is null or other defensive checks. You should do it by yourself. This is a case sensitive result.

Case insensitive :

functionvalidInput(input) {
        varALPHABET = "ABCDEFGHIJKLMNOPQRSTUWXYZ";
        for (var i = 0; i < input.length; i++) {
            var charAtI = input.charAt(i);
            var indexOfCharAtI = ALPHABET.indexOf(charAtI);
            if (indexOfCharAtI < 0) {
                returnfalse;
            }
        }
        returntrue;
    }

Case insensitive :

functionvalidInput(input) {
        varALPHABET = "ABCDEFGHIJKLMNOPQRSTUWXYZ";
        for (var i = 0; i < input.length; i++) {
            var charAtI = input.charAt(i);
            charAtI = charAtI.toUpperCase();
            var indexOfCharAtI = ALPHABET.indexOf(charAtI);
            if (indexOfCharAtI < 0) {
                returnfalse;
            }
        }
        returntrue;
    }

Solution 4:

Here's an example of a function which would return true for a match or false for a mismatch. (Please note this is a case sensitive test).

varALPHABET = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
var input = 'ABOZ';

functiontestStr(str, constant){
  var matchFlag = true;
  var strSplit = str.split("");
  for(var i=0; i<strSplit.length;i++){
    if(constant.indexOf(strSplit[i]) == -1){
       matchFlag = false;
    }
  }
  return matchFlag;
} 
alert(testStr(input, ALPHABET)); //TRUE

DEMO