asked on

autochecking checkbox based on form field being filled in

hi all,
I have a page that contains a quantity field as well as an 'add' checkbox field that users use to add the item to their shopping cart. I want to get rid of this checkbox requirement by having it autocheck when a value is entered in to the quantity field. What would be the correct syntax to do this?

Here's a code snippet that's currently on the page:

<input type="text" name="Qty" size="4" maxlength="4" value="">

<input type="checkbox" name="AddBook" value="#ISBN#"> I need this form element to both autocheck when a form quantity field is entered in. I also need this checkbox to be hidden as well.

Thanks!

justinbillig

justinbillig

ASKER CERTIFIED SOLUTION

RozanaZ

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Zyloch

Hi bluskyGuy,

Something like this?

I guess you would call this on onchange inside the textbox, like this: checkTxtField(this);

function checkTxtField(obj) {
for (var i=0;i<obj.form.elements.length;i++) {
if (obj.form.elements[i]==obj) {
if (obj.value!="") {
obj.form.elements[i+1].checked=true;
obj.form.elements[i+1].style.visibility='hidden';
} else {
obj.form.elements[i+1].checked=false;
obj.form.elements[i+1].style.visibility='visible';
}
break;
}
}
}

Regards,
Zyloch

ldbkutty

without a trim you will get checked even if you enter a white space in the textbox. you will need both onkeyup as well as onchange event (to make sure the checkbox is checked even if copy, paste the values in the textbox).

<html>
<head>
<script language="JavaScript" type="text/javascript">

</script>
</head>
<body>
<form name="myform" method="post" action="" >
Quantity: <input type="text" name="Qty" size="4" maxlength="4" value="" onkeyup="makeChecked()" onchange="makeChecked()"/> <br>
Add: <input type="checkbox" name="AddBook" value="#ISBN#"/>
</form>
</body>
</html>

RozanaZ

yes, I agree with ldbkutty
trim should be used

<HTML>
<HEAD>
<TITLE></TITLE>
<script>
function test(obj, checkId)
{
if (obj.value.trim != "")
{
document.getElementById(checkId).checked = true;
}
else
{
document.getElementById(checkId).checked = false;
}
}
</script>
</HEAD>
<BODY>
<form>
<input type="checkbox" name="AddBook" id="book1" value="#ISBN#" style="display:none">
<input type="text" name="Qty" size="4" maxlength="4" value="" onChange="test(this, 'book1')">
<br>
<input type="checkbox" name="AddBook" id="book2" value="#ISBN#" style="display:none">
<input type="text" name="Qty" size="4" maxlength="4" value="" onChange="test(this, 'book2')">
<br>
<input type="checkbox" name="AddBook" id="book3" value="#ISBN#" style="display:none">
<input type="text" name="Qty" size="4" maxlength="4" value="" onChange="test(this, 'book3')">
</form>
</BODY>
</HTML>

RozanaZ

bluskyGuy ,
Do you want a number validation for quantity field?

bluskyGuy

ASKER

Thanks all for the recommendations. I'm giving them a shot now.
If you could give me a number validation for the quantity field that would be great!
Thanks again!

RozanaZ

<HTML>
<HEAD>
<TITLE></TITLE>
<script>
function test(obj, checkId)
{
              if (isNaN((obj.value)))
              {
                  alert("Numbers only");
                  obj.focus();
                  return;
              }
              if (obj.value != "")
{

document.getElementById(checkId).checked = true;
}
else
{
document.getElementById(checkId).checked = false;
}
}
</script>
</HEAD>
<BODY>
<form>
<input type="checkbox" name="AddBook" id="book1" value="#ISBN#" style="display:none">
<input type="text" name="Qty" size="4" maxlength="4" value="" onChange="test(this, 'book1')">
<br>
<input type="checkbox" name="AddBook" id="book2" value="#ISBN#" style="display:none">
<input type="text" name="Qty" size="4" maxlength="4" value="" onChange="test(this, 'book2')">
<br>
<input type="checkbox" name="AddBook" id="book3" value="#ISBN#" style="display:none">
<input type="text" name="Qty" size="4" maxlength="4" value="" onChange="test(this, 'book3')">
</form>
</BODY>
</HTML>

bluskyGuy

ASKER

For some reason the checkboxes aren't autochecking themselves.
I'm using this for the qty field syntax:
<input type="text" name="Qty" size="4" maxlength="4" value="" onchange="if(this.value != ''){ formname.AddBook.checked=true;}else{formname.AddBook.checked=false;}">

Any suggestions?

bluskyGuy

ASKER

the autocheckbox is now working! The issue that I notice is that the user has to click out of the qty field box in order for the checkbox to be checked...do you know how to make it so that as soon as a number is entered in the checkbox is checked?

bluskyGuy

ASKER

Nevermind, i solved the problem!
Thanks everyone for the help!