Convert Salesforce Ids from 15 to 18 characters using Javascript

I figured this will be useful for anybody working with Salesforce. I used this within Netsuite and worked beautifully.

Here’s the code:

function convertSFDC15To18(sfdcID15){

if (sfdcID15.length == 15) {

var s = "";

for (var i = 0; i < 3; i++) {

var f = 0;

for (var j = 0; j < 5; j++) {

var c = sfdcID15.charAt(i * 5 + j);

if (c >= "A" && c <= "Z")

f += 1 << j;

}

s += "ABCDEFGHIJKLMNOPQRSTUVWXYZ012345".charAt(f);

}

return sfdcID15 + s;

} else {

throw "Error : " + sfdcID15 + " has not a length of 15 characters. Current length detected: " + sfdcID15.length + " characters.";

}

//Example:

var sfdc18 = convertSFDC15To18('5003000000D8cuI'); // Returns 5003000000D8cuIAAR