Curtis wrote:
bizt wrote:
>I am using the following function to validate a forms value as an
integer
function isNumeric(str){
var numericExpression = /^[0-9]+$/;
if(str.match(numericExpression)){
return true;
}else{
return false;
}
}
I need one to validate a forms value as a float number. I understand
that it should just simply be a change to the value of the
numericExpression variable but Im not too good with expression. Ive
tried doing some searches on google but either couldnt find the
relevant function or they just didnt work. Can anyone help? Thanks
Technically, if something is numeric, it shouldn't matter if it's a
float or not. However, you might try:
function isInteger(num) {
if ( !isNaN(num) ) {
return parseInt(num) == parseFloat(num) ? true : false;
}
else {
return false;
}
}
That is not going to provide a correct result. Remember that parseInt()
without second argument parses the string based on its prefix: "0x" as
hexadecimal, "0" as octal (implementation-dependent; JavaScript 1.8 still
does it, though), other numerics as decimal, and non-numeric as NaN -- which
is the reason why we usually recommend parseInt(..., 10) in scripts.
parseFloat(), on the other hand, parses every value as a decimal value and
returns `NaN' if it cannot be interpreted as such. So for example
!isNaN("0123")
evaluates to `true', but
parseInt("0123") == parseFloat("0123")
evaluates to `false' (because 83 != 123), although the value clearly can be
considered an integer.
And finally, the `==' operation results in a boolean value already. The
conditional operation is superfluous and inefficient in such a case; that
would seem to apply for all programming languages that have it.
function isFloat(num) {
if ( !isNaN(num) ) {
if ( /\.0+$/.test(num) ) {
return true;
}
else {
return parseInt(num) != parseFloat(num) ? true : false;
}
}
else {
return false;
}
}
Obvious by now, this test is equally flawed. ISTM it can be replaced safely
with
function getDecimals(num)
{
return num % 1;
}
While the return value is of type `number' and not of type `boolean' here,
it suffices for implicit type conversion later. Incidentally, it does not
make much sense to test an ECMAScript Number value for being a
floating-point value, because *all* ECMAScript Number values are IEEE-754
double-precision [64-bit] floating-point values.
Guess I couldn't entirely eliminate regex.
Guess you haven't RTFM, the FAQ, or the Specification.
PointedEars
--
var bugRiddenCrashPronePieceOfJunk = (
navigator.userAgent.indexOf('MSIE 5') != -1
&& navigator.userAgent.indexOf('Mac') != -1
) // Plone, register_function.js:16
