Question

I am trying to use this function:

function storagecalc(){
var thediv=document.forms["boxes"];
var boxno=thediv.elements["numbofboxes"];
var howmany =0;    //If the textbox is not blank    */
if(boxno.value!="")    
{        
howmany=parseInt(quantity.value);    
}
return howmany;
document.getElementById('numberprice').innerHTML = "£"+howmany;
}

To grab a value entered here:

<form action="" id="boxes">

<input type="text" id="numbofboxes" value="" name="boxnumber"/>

<button id="smtbxno" onclick="storagecalc">

<img src="images/tick.gif" alt="proceed"/>

</button>

</form>

and display it here:

<div id="grandtotal">

<p class="calctitles">

Grand Total

</p>

<p id="numberprice">

</p>

</div>

Nothing is happening when I enter a value into the textbox and click the button, is this because the button also has jQuery that hides itself and the text box upon clicking?
If not any suggestions for why it won’t work?

Answer 1

If I hide a text input element with javascript, can other javascript functions still access a value entered into it?

Every piece of javascript that can obtain a reference to the input element (via a variable, with a DOM selector) can access its value. The visibility of that element has no effect on any of those actions. Only if you would detach it from the DOM, other functions could not select it with DOM methods.

---

OK, there are some errors in the document you gave us:

• <button onclick="storagecalc"> does not execute anything, you will need to call the function: <button onclick="storagecalc();">. Only when assigning a listener to the onclick property with js, the function object needs to be used (document.getElementById("smtbxno").onclick = storagecalc;).
• In the function itself, you use a variable quantity which is undefined (and throws an exception). I’m not sure how to fix that.