>> ...
>> I am having problems at my website the people are sometimes entering
>> strings into fields that will be calculated with later on in MySQL
>> (currency units). I know there are other solutions to checking if a
>> value is a number (including JavaScript), but I do not want to use
>> another solution just for this.
>
>This is really a data validation problem and is best handled
>BEFORE the data goes into the database. Presumably, you have
>some sort of CGI script that accepts the data from the form,
>possibly processes it and then puts it in the database. This
>is probably the place to validate the data. If anything fails
>the form can be represented...
>--
I agree, a database is supposed to be designed with integrity in mind,
thus, numbers should go into number fields. I use Javascript to check for
valid numbers, the feed back to the user is instant and reliable. An
example of a javascript function to validate numeric data (includes range
checking):
<HEAD>
<SCRIPT >
<!--
function rangeCheck( oInput1, nT_min, nT_max, cLabel )
{
var lnInput = parseFloat(oInput1.value);
var lnMax = parseFloat(nT_max);
var lnMin = parseFloat(nT_min);
if( isNaN( lnInput ) )
{
alert( cLabel + " Must Be A Valid Number" );
//reset value to blank
oInput1.value = "";
oInput1.focus();
oInput1.select();
}
else
{
if( lnInput < lnMin && lnMin!=999 )
{
alert( cLabel + " must be greater than " + nT_min );
//reset value to blank
oInput1.value = "";
oInput1.focus();
oInput1.select();
}
else
{
if( lnInput > lnMax && lnMin!=999 )
{
alert( cLabel + " must be less than " + nT_max );
//reset value to blank
oInput1.value = "";
oInput1.focus();
oInput1.select();
}
}
}
}
//-->
</SCRIPT>
</HEAD>
<BODY>
<form NAME="form1">
<input NAME="input1" HEIGHT="23" WIDTH="25" SIZE="5" VALUE="3.2"
onchange="rangeCheck( this, '0.5', '6.5', 'Input 1 Error: ' )">
</form>
</BODY>
Christopher R. Jones, P.Eng.
14 Oneida Avenue
Toronto, Ontario M5J 2E3
Tel. 416 203-7465
Fax. 416 203-3044
Email cj@stripped
