Take a value 1-31 and convert it to ordinal date w/ JavaScript

Question

Is there a JavaScript code snippet to take a value of 1-31 and convert it to 1st, 2nd, 3rd, etc?

Thanks!

Answer 1

function getOrdinal(n) {
    var s=["th","st","nd","rd"],
    v=n%100;
    return n+(s[(v-20)%10]||s[v]||s[0]);
}

Thanks @RobG bit modified version

function getOrdinal(n) {
    if((parseFloat(n) == parseInt(n)) && !isNaN(n)){
        var s=["th","st","nd","rd"],
        v=n%100;
        return n+(s[(v-20)%10]||s[v]||s[0]);
    }
    return n;     
}

Tests

getOrdinal("test");   // test
getOrdinal(1.5);      // 1.5
getOrdinal(1);        // 1st
getOrdinal(2);        // 2nd
getOrdinal(3);        // 3rd
getOrdinal(4);        // 4th
getOrdinal(true);     // true
getOrdinal(Infinity); // Infinity
getOrdinal(NaN);      // NaN
getOrdinal(void 0);   // undefined