Get all the input js code under the form

Use the collection object elements of the form to get the value

 
var form = document.getElementById("dateform"); 
var a = form.elements.length;//Number of all controls
for (var j=0;j<a;j++){ 
if(form.elements[j].className == "text"){//Class = "text" of the control
if(form.elements[j].value=="" || form.elements[j].value==null){ 
alert(" Can't be empty "); 
form.elements[j].focus(); 
return false; 
} 
} 
}