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Old November 25th, 2004, 11:12 AM
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Default Decimal check

Hi Guys,
Can anyone pls tell me how can I check if the number input by user is decimal if it is then it should only be upto 2 decimal places.

I can check if it is decimal by isdecimal() but how can I check the number of digits from decimal point.

Any help would be very much appreciate.
cheers


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Old November 25th, 2004, 11:30 AM
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Hi,

One way is to use a regular expression - just pass the number & required decimal places to this method...
Code:
function CheckDecimal(pNum, pDp){
    return new RegExp("^\\d*\\.\\d{0," + pDp + "}$").test(pNum);
}
HTH,

Chris

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Old November 25th, 2004, 11:48 AM
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Default

Good idea, perhaps with a minus?
Code:
"^-?\\d*\\.\\d{0," + pDp + "}$"

--

Joe (Microsoft MVP - XML)
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Old November 25th, 2004, 11:51 AM
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Default

Hi Chris,
The function which you mentioned:
function CheckDecimal(pNum, pDp){
    return new RegExp("^\\d*\\.\\d{0," + pDp + "}$").test(pNum);

Since I need two decimal places does that infer that pdp = 2
and what does "d" stand in RegExp .
Is test and RegExp inbuilt functions in JavaScript.
Waiting for reply.


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Old November 25th, 2004, 12:03 PM
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Hi,

Yep, make pDp = 2 for 2 decimal places.

\d means a decimal character in regular expression syntax, but as it's being passed to the expressions constructor as a string, it needs to be escaped and hence becomes \\d.

new RegExp creates a regular expression object and test is one of it's methods/functions - well worth checking out if you're going to do much in the way of string manipulation or validation.

Cheers,

Chris





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