Question

I have used the following javascript code to generate different numbers if the last letter of an element is a letter or 1. But somehow the whole time else is executed whether it includes letters or not. Where is my mistake??

if (document.getElementById(element)!=null && element.charAt(element.length-1)==/^[a-zA-Z]*$/) {
    var element = element+1;
}
else if (element.charAt(element.length-1)==1) {
    var element = element;
    var lastletter = element.charAt(element.length-1);
    lastletter++;
    var element = element.substring(0, element.length-1)+lastletter;
}
else {
    var element = element;
}

Answer 1

Use match to find substing with regular expression.

Fixed code:

if (document.getElementById(element) && 
    element.match(/[A-z]$/) { // <========
    var element = element+1;
}
else if (element[element.length - 1]) === '1') {  // <========
    var element = element;
    var lastletter = element.charAt(element.length-1);
    lastletter++;
    var element = element.substring(0, element.length-1)+lastletter;
}
else {
    var element = element;
}​

Note that your variable naming are confusing. you better change from element to elementId.