Question

I’m new to Javascript and trying to learn some basics.

Can you please check if I had done the following correctly? If not, please outline what I’ve yet to do.

I had to:

• Calculate the user’s month of birth as a number where January=0 through to December=11.
• Take the string entered
• Get the substring being the first three characters
• Convert to uppercase
• Find the starting location of the three letter abbreviation in the month abbreviations string
• Divide this by 3
• (This is not the only way to find the month number, but it allows us to practice searching in a string)

My code:

var year = prompt('Enter year of birth as a 4 digit integer');  

var month = prompt('Enter the name of the month of birth');
// Chop everything after the first 3 characters and make it lowercase
month = month.substr(0,3).toLowerCase();
// Store your array in months, differently named than the month input
var months = ["jan", "feb", "mar", "apr", "may", "jun", "jul", "aug", "sep", "oct",
"nov", "dec"];  

// We then use array.indexOf() to locate it in the array
var pos = months.indexOf(month);
if (pos >= 0) {
// valid month, number is pos
}

Answer 1

Your code obviously does not follow the given instructions:

• Convert to uppercase
• Find the starting location of the three letter abbreviation in the month abbreviations string
• Divide this by 3
• …to practice searching in a string

But does meet the requirement to calculate the user’s month of birth as a number. I think array search is even superior to string search (no harm by finding strings between the month names ("anf" etc), and also faster because of not checking these possibilities), but they seem to want you to do it with their way.