How to check all text boxes are empty before clicking calculate
<p>Hi all im new to jscipt,,, well, programming in general to be honest, but learning slowly for personal use.
I seek guidence on how i could place all the textboxes(inputs) in my index file into a list container, loop through them to check if they are empty or not before clicking the calculate button. If they are empty then inform the user of which one is empty.
Also, is there a way of preventing users from entering text into the textboxes and numbers only.
Background: im creating a form that requires all fields to be populate with numbers(in hours),  a graph will then be generated from those values.
ive placed the file in skydrive for folks to download with the link below.</p>

<p><a href="http://sdrv.ms/Vj56Et" rel="nofollow">Index file</a></p>

<p>I did try the following but this alerts me regardless of weather the texboxes are populate or not.</p>

<pre><code>function checkInputsGenerateGraph()
{
if( $('#hutz-hoursInput').val() == ""||$('#hutz-weeksPerYearInput').val() ==      ""||$('#hutz-jobsPerWeekInput').val() == ""||$('#hutz-hourlyMachineRateInput').val() == ""||$('#hutz-maintneneceDowntimeInput').val() == ""||$('#hutz-scrapRateInput').val() == ""||$('#hutz-toolsPerJobInput').val() == ""||$('#hutz-timeToLoadToolInput').val() == ""||$('#hutz-timeToSetPartsInput').val() == "")
{
alert('One them is empty!!');
}
else
{
$("#hutz-graph").slideDown();  
                    $("#hutz-lblImproveMyProcess").slideUp();
                    $("#hutz-hoursInput").slideUp();
                    $("#hutz-weeksPerYearInput").slideUp();
                    $("#hutz-jobsPerWeekInput").slideUp();
                    $("#hutz-ourlyMachineRateInput").slideUp();
                    $("#hutz-ntneneceDowntimeInput").slideUp();
                    $("#hutz-scrapRateInput").slideUp();
                    $("#hutz-toolsPerJobInput").slideUp();
                    $("#hutz-timeToLoadToolInput").slideUp();
                    $("#hutz-timeToSetPartsInput").slideUp();
                    $("#hutz-lblMachineDetails").slideUp();
                    $("#hutz-lblPartSetting").slideUp();
                       $("#hutzcurrencyPreferenceInput").slideUp();
                    createChart();                      
}
}
</code></pre>
