function numbersOnly(event) {
	var keyCode = event.keyCode; 
    if (keyCode == 0) 
    	keyCode = event.which;

        if (keyCode >= 48 && keyCode <= 57 || keyCode == 8)
          return true;
        else
          return false;
      }
      
function decimalOnly(event) {
	var keyCode = event.keyCode; 
    if (keyCode == 0) 
    	keyCode = event.which;

        if (keyCode >= 48 && keyCode <= 57 || keyCode == 46 || keyCode == 8)
          return true;
        else
          return false;
      }      

function dateOnly(event) {
	var keyCode = event.keyCode; 
    if (keyCode == 0) 
    	keyCode = event.which;

        if (keyCode >= 48 && keyCode <= 57 || keyCode == 47 || keyCode == 8)
          return true;
        else
          return false;
      }  


// for jsp onblur checks where errors are to be shown
function checkEmail(emailField) {
    var valArr=emailField.value.split(";");
    var len=valArr.length;
    for (var j=0;j<len;j++) {
    
        if (!davidsCheckEmail(trim(valArr[j]), true)) {
            emailField.focus();
            return false;

        } else if (!springsCheckEmail(trim(valArr[j]))) {
            alert(emailField.name + " is an invalid email address.");
            emailField.focus();
            return false;
        }                        
    }

    return true;    

}

// for callers using the single parameter call
// assumes they just want the boolean returned
// not to show alerts or change focus       
function davidsCheckEmail (emailStr) {
    return davidsCheckEmail (emailStr, false);    
}

function davidsCheckEmail (emailStr, showError) {

    // david added the following so this function would work
    if(emailStr == ""){
        return true;
    }

    /* The following variable tells the rest of the function whether or not
    to verify that the address ends in a two-letter country or well-known
    TLD.  1 means check it, 0 means don't. */
    var checkTLD=1;

    /* The following pattern is used to check if the entered e-mail address
    fits the user@domain format.  It also is used to separate the username
    from the domain. */
    
    var emailPat=/^(.+)@(.+)$/;

    /* The following string represents the pattern for matching all special
    characters.  We don't want to allow special characters in the address. 
    These characters include ( ) < > @ , ; : \ " . [ ] */
    
    var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
    
    /* The following string represents the range of characters allowed in a 
    username or domainname.  It really states which chars aren't allowed.*/
    
    var validChars="\[^\\s" + specialChars + "\]";

    /* The following pattern applies if the "user" is a quoted string (in
    which case, there are no rules about which characters are allowed
    and which aren't; anything goes).  E.g. "jiminy cricket"@disney.com
    is a legal e-mail address. */
    
    var quotedUser="(\"[^\"]*\")";
    
    /* The following pattern applies for domains that are IP addresses,
    rather than symbolic names.  E.g. joe@[123.124.233.4] is a legal
    e-mail address. NOTE: The square brackets are required. */
    
    var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
    
    /* The following string represents an atom (basically a series of non-special characters.) */
    
    var atom=validChars + '+';

    /* The following string represents one word in the typical username.
    For example, in john.doe@somewhere.com, john and doe are words.
    Basically, a word is either an atom or quoted string. */
    
    var word="(" + atom + "|" + quotedUser + ")";
    
    // The following pattern describes the structure of the user
    
    var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
    
    /* The following pattern describes the structure of a normal symbolic
    domain, as opposed to ipDomainPat, shown above. */
    
    var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");

    /* Finally, let's start trying to figure out if the supplied address is valid. */
    
    /* Begin with the coarse pattern to simply break up user@domain into
    different pieces that are easy to analyze. */
    
    var matchArray=emailStr.match(emailPat);
    
    if (matchArray==null) {

        /* Too many/few @'s or something; basically, this address doesn't
        even fit the general mould of a valid e-mail address. */
        
        if (showError) {
            alert("Email address seems incorrect (check @ and .'s)");
        }            
        return false;
    }
    var user=matchArray[1];
    var domain=matchArray[2];

    // Start by checking that only basic ASCII characters are in the strings (0-127).
    
    for (i=0; i<user.length; i++) {
        if (user.charCodeAt(i)>127) {
            if (showError) {
                alert("The username contains invalid characters.");
            }            
            return false;
        }
    }
    for (i=0; i<domain.length; i++) {
        if (domain.charCodeAt(i)>127) {
            if (showError) { 
                alert("The domain name contains invalid characters.");
            }    
            return false;
       }
    }

    // See if "user" is valid 
    
    if (user.match(userPat)==null) {
    
        // user is not valid        
        if (showError) {
            alert("The username doesn't seem to be valid.");
        }            
        return false;
    }

    /* if the e-mail address is at an IP address (as opposed to a symbolic
    host name) make sure the IP address is valid. */
    
    var IPArray=domain.match(ipDomainPat);
    if (IPArray!=null) {
    
        // this is an IP address
        for (var i=1;i<=4;i++) {
            if (IPArray[i]>255) {
                if (showError) {
                    alert("Destination IP address is invalid!");
                }    
                return false;
            }
        }
        return true;
    }

    // Domain is symbolic name.  Check if it's valid.
     
    var atomPat=new RegExp("^" + atom + "$");
    var domArr=domain.split(".");
    var len=domArr.length;
    for (i=0;i<len;i++) {
        if (domArr[i].search(atomPat)==-1) {
            if (showError) {
                alert("The domain name does not seem to be valid.");
	        }            
            return false;
        }
    }

    /* domain name seems valid, but now make sure that it ends in a
    known top-level domain (like com, edu, gov) or a two-letter word,
    representing country (uk, nl), and that there's a hostname preceding 
    the domain or country. */

    if (checkTLD && domArr[domArr.length-1].length!=2 
        && domArr[domArr.length-1].search(knownDomPats)==-1) 
    {        
        var msg = emailStr + "\nThe above email address should end in a well-known domain or two letter country code.\n\n"
                + "Click OK to accept the email address as is.\n\n"  
                + "Otherwise, click Cancel to stop and correct it.";
        var ans = confirm(msg);
        if (ans) {
            return true;
        } 
        return false;
    }

    // Make sure there's a host name preceding the domain.

    if (len<2) {
        if (showError) {
            alert("This address is missing a hostname!");
        }            
        return false;
    }

    // If we've gotten this far, everything's valid!
    return true;
}      

/**
 * Reference: Sandeep V. Tamhankar (stamhankar@hotmail.com),
 * http://javascript.internet.com
 */
function springsCheckEmail(emailStr) {

   if (emailStr.length == 0) {
       return true;
   }
   var emailPat=/^(.+)@(.+)$/;
   var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]";
   var validChars="\[^\\s" + specialChars + "\]";
   var quotedUser="(\"[^\"]*\")";
   var ipDomainPat=/^(\d{1,3})[.](\d{1,3})[.](\d{1,3})[.](\d{1,3})$/;
   var atom=validChars + '+';
   var word="(" + atom + "|" + quotedUser + ")";
   var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
   var domainPat=new RegExp("^" + atom + "(\\." + atom + ")*$");
   var matchArray=emailStr.match(emailPat);
   if (matchArray == null) {
       return false;
   }
   var user=matchArray[1];
   var domain=matchArray[2];
   if (user.match(userPat) == null) {
       return false;
   }
   var IPArray = domain.match(ipDomainPat);
   if (IPArray != null) {
       for (var i = 1; i <= 4; i++) {
          if (IPArray[i] > 255) {
             return false;
          }
       }
       return true;
   }
   var domainArray=domain.match(domainPat);
   if (domainArray == null) {
       return false;
   }
   var atomPat=new RegExp(atom,"g");
   var domArr=domain.match(atomPat);
   var len=domArr.length;
   if ((domArr[domArr.length-1].length < 2) ||
       (domArr[domArr.length-1].length > 3)) {
       return false;
       
   }
   if (len < 2) {
       return false;
   }

   return true;
}