Solved

How do I check the contents of this textbox in my php/mysql application

Posted on 2009-04-09
4
234 Views
Last Modified: 2012-05-06
I have the attached checkbox section in my code.  Each checkbox has a value attached to it and calls the attached function which tallys everything and displays it in another textbox.  The client wanted me to add a Quantity box that will multiple anything selected by whatever the user puts in the quantity textbox.  I got that to work, but i want to check if the box is empty,and if empty, make the value 1,  or check if the value entered is a non-numeric value before it does the calculation.  I thought this would be simple, but I am too brain drained to get this working.  

I get this error in FF:
document.getElementById("Q_379") is null
[Break on this error] if (document.getElementById('Q_379').value == "")

Help please
function calc(theForm)
{
  //debugger;
  var elements = theForm.elements;
  var total = 0;
  var multiplier=1;
  var imgQty = 0;
  var imgTotal = 0;
  var photoQty = 0
  for(var i=0; i<elements.length; i++)
  {
      var element = elements[i];
  
        if(element.type == 'checkbox' && element.checked)
        {
            total += parseFloat(element.value);
        }
 
        else if(element.name=="Q_361" && element.checked)
        {
            multiplier = parseFloat(element.value);
        }
        if (document.getElementById('Q_379').value == "")
        {
        	projQtyBox = 1;
        }
        else
        {       
			projQtyBox = document.getElementById('Q_379').value;
        }
        
  document.getElementById('Q_330').value = total*multiplier*projQtyBox;
  
}
}

Open in new window

checkbox.JPG
0
Comment
Question by:justmelat
  • 2
4 Comments
 
LVL 16

Accepted Solution

by:
robinu earned 400 total points
ID: 24111708
Probably because the new textbox you added does not have the id 'Q_379' but it's its name.

0
 
LVL 19

Expert Comment

by:Michael701
ID: 24112422
I hope that quantity box is large enough. Ok, just kidding, it's been one of those days.

And could you be any less descriptive with your element names?

Here's a snippet when I mulitply quantity and price of an item.
    if (isNaN(quantity))
    {
      error=1
      notes.innerHTML="Invalid quantity!"
    }
    else if (isNaN(price))
    {
      error=1
      notes.innerHTML="Invalid price!"
    }
    else
    {
    answer=quantity * price
    ....
    }

Open in new window

0
 
LVL 19

Expert Comment

by:Michael701
ID: 24112429
oh guess I should have also shown the variable definitions

  for (x=1; x<=<?PHP echo MAX_ORDER_LINES ?>; x++)
  {
    quantity=document.getElementById("quantity_"+x).value
    price=document.getElementById("price_"+x).value
    extension=document.getElementById("extension_"+x)
    notes=document.getElementById("notes_"+x)

Open in new window

0
 
LVL 1

Author Comment

by:justmelat
ID: 24117236
Ahhh, can't believe i didn't see that. thank you.
0

Featured Post

Announcing the Most Valuable Experts of 2016

MVEs are more concerned with the satisfaction of those they help than with the considerable points they can earn. They are the types of people you feel privileged to call colleagues. Join us in honoring this amazing group of Experts.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article demonstrates how to create a simple responsive confirmation dialog with Ok and Cancel buttons using HTML, CSS, jQuery and Promises
Boost your ability to deliver ambitious and competitive web apps by choosing the right JavaScript framework to best suit your project’s needs.
The viewer will learn how to dynamically set the form action using jQuery.
This tutorial will teach you the core code needed to finalize the addition of a watermark to your image. The viewer will use a small PHP class to learn and create a watermark.

808 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question