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Is it a number?

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Jul 28.2004

Can anyone tell me how to test whether

event.srcElement.value

is a number?

Thanks for any help.

to post a comment
JavaScript

5 Comments(s) ↴

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@BillyRayJul 28.2004 — if (!isNaN(event.srcElement.value)) alert('It\'s a number!');

Hope this helps,

Dan
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@WebskaterauthorJul 28.2004 — Thanks for your answer.
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@steelersfan88Jul 28.2004 — Webskater ... remember never to forget using [font=monospace]document.[/font] when referencing a form element.
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@compuboy1010Oct 27.2004 — What about this function? It doesn't work:

function checkBirtdate(form) {

if (!form.birthday.value) || !form.birthmonth.value || !form.birthyear.value) {

alert("Please enter your birthdate.");

form.birthday.focus();

return false;

} else if (isNaN(form.birthday.value) || isNaN(form.birthmonth.value ) || isNaN(form.birthday.value)){

alert("Please enter a valid birthdate Format TT/MM/JJJJ ein ?");

form.birthday.focus();

return false;

} else {

return true;

}

}
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@baconbuttyOct 27.2004 — Some thoughts:


if (!form.birthday.value) || !form.birthmonth.value || !form.birthyear.value)

[B]LOOKS LIKE AN EXTRA BRACKET ON THE FIRST CONDITION[/B]

{

alert("Please enter your birthdate.");

form.birthday.focus();

return false;
[/QUOTE]


if (isNaN(form.birthday.value) || isNaN(form.birthmonth.value ) || isNaN(form.birthday.value))
[/QUOTE]

As I understand it "NaN" is a special value in Javascript, and isNaN tests for that value. I don't think you can use it generally (others, I am sure you will correct me if I am wrong). You need to do something to obtain it. Thus try the following:-

[CODE]

if (isNaN(parseInt(form.birthday.value)) || isNaN(parseInt(form.birthmonth.value)) || isNaN(parseInt(form.birthday.value))

[/CODE]

Of course the above offers only limited validation, and you may wish to explore using regular expressions to validate your form.
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