JavaScript - For Statement To Update Variable If More Than 3 Checkboxes Selected

function checkform ( form )
{

  if (form.contact_name.value == "contact name") {
    alert( "Please enter a contact name" );
    form.contact_name.focus();
    return false ;
  }
  
  if (form.last_name.value == "agency/company name") {
    alert( "Please enter agency/company name" );
    form.last_name.focus();
    return false ;
  }

  if (form.email.value == "email address") {
    alert( "Please enter contact email address" );
    form.email.focus();
    return false ;
  }
  
    if (form.telephone.value == "dates required") {
    alert( "Please enter dates required" );
    form.telephone.focus();
    return false ;
  }
  
      if (form.comments.value == "any other info") {
    alert( "Please enter more information" );
    form.comments.focus();
    return false ;
  }
  
    if (form.contact_name.value == "") {
    alert( "Please enter a contact name" );
    form.contact_name.focus();
    return false ;
  }
  
  if (form.last_name.value == "") {
    alert( "Please enter agency/company name" );
    form.last_name.focus();
    return false ;
  }

  if (form.email.value == "") {
    alert( "Please enter contact email address" );
    form.email.focus();
    return false ;
  }
  
    if (form.telephone.value == "") {
    alert( "Please enter dates required" );
    form.telephone.focus();
    return false ;
  }
  
      if (form.comments.value == "") {
    alert( "Please enter more information" );
    form.comments.focus();
    return false ;
  }

  return true ;
}
//-->
</script>

<form name="contactform" method="post" action="send_form_email.php" onsubmit="return checkform(this);">
<table width="450px">
</tr>
<tr>

 <td valign="top">
  <input  class="formbox" type="text" STYLE="text-align:right" value="contact name" name="contact_name" maxlength="50" size="30" onblur="if (this.value == '') {this.value = 'contact name';}"  onfocus="if (this.value == 'contact name') {this.value = '';}">
 </td>
</tr>
 
<tr>

 <td valign="top">
  <input class="formbox" type="text" STYLE="text-align:right" value="agency/company name" name="last_name" maxlength="50" size="30" onblur="if (this.value == '') {this.value = 'agency/company name';}"  onfocus="if (this.value == 'agency/company name') {this.value = '';}">
 </td>
</tr>
<tr>

 <td valign="top">
  <input class="formbox" type="text" STYLE="text-align:right" value="email address" name="email" maxlength="80" size="30" onblur="if (this.value == '') {this.value = 'email address';}"  onfocus="if (this.value == 'email address') {this.value = '';}">
 </td>
 
</tr>
<tr>

 <td valign="top">
  <input class="formbox" type="text" STYLE="text-align:right" value="dates required" name="telephone" maxlength="30" size="30" onblur="if (this.value == '') {this.value = 'dates required';}"  onfocus="if (this.value == 'dates required') {this.value = '';}">
 </td>
</tr>

<tr>
<td>
<div id="checksdiv">
Full Day<input class="formcheck" type="checkbox" name="check[]" value="Full_Day">
Half Day<input class="formcheck" type="checkbox" name="check[]" value="Half Day">
Hourly <input class="formcheck" type="checkbox" name="check[]" value="Hourly">
</div>

</td>
</tr>



<tr>

 <td valign="top">
  <textarea class="formbox" name="comments" value="any other info" STYLE="text-align:right" maxlength="1000" cols="25" rows="6" onblur="if (this.value == '') {this.value = 'any other info';}"  onfocus="if (this.value == 'any other info') {this.value = '';}"></textarea>
 </td>
 
</tr>
<tr>
 <td colspan="2" style="text-align:right">
  <input type="image" value="Submit" src="images/submit.png" />
 </td>
</tr>
</table>
</form>

<script language="JavaScript">
	function checkForNone() {
		checked=false;
		for (i=0,n=selectForm2.elements.length;i<n;i++) {
		  if (document.selectForm2.getElementById("check_"+String(i)).checked || document.selectForm2.getElementById("check2_"+String(i)).checked ) {
		    checked=true;
		  }
		}  
		if (checked==true) {
		  alert("OK!");
		  return true;
		}
		else {
		  alert("Please select at least one checkbox.");
		  return false;
		}
	}
	</script>

/***
**** INSERT INTO TABLE ** 
***/
function prePopulate(){
	BMIDB.transaction(
	    function (transaction) {
		//Starter data when page is initialized
		var data = ['1','','14','0','0',''];  
		
		transaction.executeSql("INSERT INTO page_settings(id, fname, age, height, weight, gender, date) VALUES (?, ?, ?, ?, ?, ?, ?)", [data[0], data[1], data[2], data[3], data[4], data[5], data[6]]);
	    }
	);	
}



/***
**** UPDATE TABLE ** 
***/
function updateSetting(){
	BMIDB.transaction(
	    function (transaction) {
	    	if($('#fname').val() != '') {
	    		var fname = $('#fname').val();
	    	} else {
	    		var fname = '';
	    	}
			
			var age    = $('#age').val();
			var height  = $('#height').val();
			var weight   = $('#weight').val();
			var gender   = $('#gender').val();
			var date   = $('#date').val();
			
	    	
	    	transaction.executeSql("UPDATE page_settings SET fname=?, age=?, height=?, weight=?, gender=?, date=? WHERE id = 1", [fname, age, height, weight, gender, date]);
	    }
	);	
		selectAll();
}
function selectAll(){ 
	BMIDB.transaction(
	    function (transaction) {

	        transaction.executeSql("SELECT * FROM page_settings;", [], dataSelectHandler, errorHandler);
	        
	    }
	);	
}

function dataSelectHandler(transaction, results){

	// Handle the results
    for (var i=0; i<results.rows.length; i++) {
        
    	var row = results.rows.item(i);
    	
        var newFeature = new Object();
    	
    	newFeature.fname   = row['fname'];
        newFeature.age	   = row['age'];
        newFeature.height  = row['height'];
        newFeature.weight  = row['weight'];
        newFeature.gender  = row['gender'];
        newFeature.date  = row['date'];
        
        
        newFeature.height2 = newFeature.height / 100
  		newFeature.BMI = newFeature.weight  / (newFeature.height2 * newFeature.height2)
        
        BMI = newFeature.BMI;
		bmiresult = BMI.toFixed(3);
        
        $('body').css('font-family',newFeature.height);
        $('#content').html('<h4 id="your_weight">'+ newFeature.fname +' your BMI is: </h4><span>'+ bmiresult +'</span>');
        
        if(newFeature.fname != '') {
       		$('#greeting').html('Hi '+newFeature.fname+'!');
       		$('#fname').val(newFeature.fname);
        } 
        
       $('#height').val(newFeature.height);
       $('select#age').find('option[value='+newFeature.age+']').attr('selected','selected');  
       $('#weight').val(newFeature.weight);
       $('select#gender').find('option[value='+newFeature.gender+']').attr('selected','selected');

       
    }

}





/***
**** Save 'default' data into DB table **
***/

function saveAll(){
		prePopulate(1);
}


function errorHandler(transaction, error){
 	if (error.code==1){
 		// DB Table already exists
 	} else {
    	// Error is a human-readable string.
	    console.log('Oops.  Error was '+error.message+' (Code '+error.code+')');
 	}
    return false;
}


function nullDataHandler(){
	console.log("SQL Query Succeeded");
}

/***
**** SELECT DATA **
***/
function selectAll(){ 
	BMIDB.transaction(
	    function (transaction) {
	        transaction.executeSql("SELECT * FROM page_settings;", [], dataSelectHandler, errorHandler);
	    }
	);	
}