Reg Expression for currency

[johkar]

I need a regular expression to format U.S. currency as 1,215.25 (commas
and decimals)...if it is not already in that format. It should also
allow a '-' sign as the first character for negative numbers. I have
looked in the FAQ and through this group, plus the net and cannot seem
to find the right example.

Any pointers or solutions appreciated. Thanks. I found the below
posted in this group:

<script type="text/javascript">
var RgX = /^\$(\d{1,3}(\,\d{3})*|(\d+))(\.\d{2})?$/

function NewComma(Q) { Q = String(Q)
return (Q == (Q=Q.replace(RgX, "$1$2,$3"))) ? Q : NewComma(Q)
}

function setFormat(elm){
var frmCurr= NewComma(elm);
alert(frmCurr);
}

setFormat(121525);
</script>

[TheBagbournes]

johkar wrote:

I need a regular expression to format U.S. currency as 1,215.25 (commas
and decimals)...if it is not already in that format. It should also
allow a '-' sign as the first character for negative numbers. I have
looked in the FAQ and through this group, plus the net and cannot seem
to find the right example.

function format(c)
{
if (typeof c != "string")
c = new String(c);
c = parseFloat(c.split(",").join("").
replace(/^\$/, "")).toFixed(2).toString();
var t = /(\d)(\d{3})([\.\,])/;
for (;;)
{
o = c;
c = c.replace(t, "$1,$2$3");
if (o == c)
break;
}
return c;
}
alert(format("$1,456,789.12"));
alert(format("$1,456,789.129"));
alert(format(-167));
alert(format(20.3));

[johkar]

TheBagbournes wrote:

johkar wrote:

I need a regular expression to format U.S. currency as 1,215.25 (commas
and decimals)...if it is not already in that format. It should also
allow a '-' sign as the first character for negative numbers. I have
looked in the FAQ and through this group, plus the net and cannot seem
to find the right example.

function format(c)
{
if (typeof c != "string")
c = new String(c);
c = parseFloat(c.split(",").join("").
replace(/^\$/, "")).toFixed(2).toString();
var t = /(\d)(\d{3})([\.\,])/;
for (;;)
{
o = c;
c = c.replace(t, "$1,$2$3");
if (o == c)
break;
}
return c;
}
alert(format("$1,456,789.12"));
alert(format("$1,456,789.129"));
alert(format(-167));
alert(format(20.3));

Perfect, thank you. Still analyzing what every line does.

[Thomas 'PointedEars' Lahn]

TheBagbournes wrote:

johkar wrote:

I need a regular expression to format U.S. currency as 1,215.25 (commas
and decimals)...if it is not already in that format. It should also
allow a '-' sign as the first character for negative numbers. I have
looked in the FAQ and through this group, plus the net and cannot seem
to find the right example.
function format(c)
{
if (typeof c != "string")

Indent (posted) code with spaces, not tabs.
c = new String(c);
No new String object needs to be created for type conversion.
c = parseFloat(c.split(",").join("").
There is no point in split("...").join("") if you can use replace().
There is no point in removing the format first, and then rebuilding
it, if it is already perfect.
replace(/^\$/, "")).toFixed(2).toString();
There is no point in removing a leading `$' but not including it in
the result again. There is no point in toFixed(2).toString(), since
toFixed(...) already returns a string value.
var t = /(\d)(\d{3})([\.\,])/;
Neither the dot nor the comma character needs to be escaped in a
character class. In fact, escaping a special character in a character
class could have the opposite meaning (it does not have in ECMAScript).
for (;;)
{
o = c;
c = c.replace(t, "$1,$2$3");
if (o == c)
break;
}
return c;
}

At least:

function format(n)
{
if (typeof n != "string") n = String(n);

if (!/^\$?(\d{1,3},)*\d{3}.\d\d$/.test(n))
{
n = parseFloat(n.replace(/,|^\$/g, "")).toFixed(2);

var rx = /(\d)(\d{3})([.,])/;

while (rx.test(n))
{
n = n.replace(rx, "$1,$2$3");
}

n = "$" + n;
}

return n;
}
PointedEars
--
Multiple exclamation marks are a sure sign of a diseased mind.
-- Terry Pratchett