Javascript - Multiple Arrays containing Variables
<p>I'm new to Javascript and finding some difficulty in a task writing a program.</p>

<p>My task will be to write a program that will allow a user to enter their date of birth. The program then proceeds to give the corresponding Chinese Zodiac sign in an image and the number of days the user has been alive.</p>

<p><strong>What will be input?</strong></p>

<ul>
<li>The user's year of birth (assume a valid 4 digit year will be input)</li>
<li>The user's month of birth (assume user will enter at least the first
three letters of a month name, but this could be longer and could
contain upper case characters, so it could be jan, Jan, january, or
January, or other month names)</li>
<li>The user's date (in the month) of birth (assume a valid date will be
entered)</li>
</ul>

<p><strong>Constants we will use</strong></p>

<p>Create and appropriately name constants to store the following values:</p>

<ul>
<li>A string containing month
abbreviations    'JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC'</li>
<li>The number of milliseconds in a day  1000*60*60*24</li>
<li>The cycle of Chinese zodiac  12</li>
<li>The year initialising Chinese Zodiac cycles  1924</li>
</ul>

<p><strong>My code so far:</strong></p>

<pre><code>var year = prompt('Enter year of birth as a 4 digit integer') // A prompt to enter the year of birth.
var month = prompt('Enter the name of the month of birth') // A prompt to enter the month of birth.
var date = prompt('Enter day of birth as an integer') // A prompt to enter the date of birth.
    var month = ["jan", "feb", "mar", "apr", "may", "jun", "jul", "aug", "sep", "oct", "nov", "dec"]
    var month = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
    var month = ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"]
    var month = ["january", "february", "march", "april", "may", "june", "july", "august", "september", "october", "november", "december"]
</code></pre>

<p>I'm having trouble with the input of the month of birth. I'm trying to write a code to assume user will enter at least the first three letters of a month name, but this could be longer and could contain upper case characters, so it could be jan, Jan, january, or January, or other month names.</p>

<p>Any help will be appreciated! </p>

<p>George</p>
