请问各位，判断是否数字型的JavaScript函数是什么？

[kevinsun]

请问各位，判断是否数字型的JavaScript函数是什么？

[King]

没有现成的，一般是把输入作为字符串，一个一个字符判定是不是不小于'1'和不大于'0'，再判断长度。

[yaya]

Do you want IsNaN

Description
Determines whether a value is the reserved value NaN (not a number).
Syntax
isNaN(numvalue)
The numvalue argument is the value to be tested against NaN.


Remarks

The isNaN function returns true if the value is NaN, and false otherwise. You typically use this function to test return values from the parseInt and parseFloat methods.
Alternatively, a variable could be compared to itself. If it compares as unequal, it is NaN. This is because NaN is the only value that is not equal to itself.

yaya

[leslielu]

function isdigit(s)
{
var r,re;
re = /\d*/; //\d表示数字,*表示匹配多个数字
r = s.match(re);

return (r==s)?1:0;
}
Character Description
\ Marks the next character as special. /n/ matches the character "n". The seque
nce /\n/ matches a linefeed or newline character.
^ Matches the beginning of input or line.
$ Matches the end of input or line.
* Matches the preceding character zero or more times. /zo*/ matches either "z"
or "zoo."
+ Matches the preceding character one or more times. /zo+/ matches "zoo" but no
t "z."
? Matches the preceding character zero or one time. /a?ve?/ matches the "ve" in
"never."
. Matches any single character except a newline character.
(pattern) Matches pattern and remembers the match. The matched substring can be
retrieved from the result Array object elements [1]...[n] or the RegExp object's
$1...$9 properties. To match parentheses characters ( ), use "\(" or "\)".
x|y Matches either x or y. /z|food?/ matches "zoo" or "food."
{n} n is a nonnegative integer. Matches exactly n times. /o{2}/ does not match t
he "o" in "Bob," but matches the first two o's in "foooood."
{n,} n is a nonnegative integer. Matches at least n times. /o{2,}/ does not mat
ch the "o" in "Bob" and matches all the o's in "foooood." /o{1,}/ is equivalent t
o /o+/.
{n,m} m and n are nonnegative integers. Matches at least n and at most m times.
/o{1,3}/ matches the first three o's in "fooooood."
[xyz] A character set. Matches any one of the enclosed characters. /[abc]/ matc
hes the "a" in "plain."
[^xyz] A negative character set. Matches any character not enclosed. /[^abc]/ m
atches the "p" in "plain."
\b Matches a word boundary, such as a space. /ea*r\b/ matches the "er" in "neve
r early."
\B Matches a nonword boundary. /ea*r\B/ matches the "ear" in "never early."
\d Matches a digit character. Equivalent to [0-9].
\D Matches a nondigit character. Equivalent to [^0-9].
\f Matches a form-feed character.
\n Matches a linefeed character.
\r Matches a carriage return character.
\s Matches any white space including space, tab, form-feed, and so on. Equivale
nt to [ \f\n\r\t\v]
\S Matches any nonwhite space character. Equivalent to [^ \f\n\r\t\v]
\t Matches a tab character.
\v Matches a vertical tab character.
\w Matches any word character including underscore. Equivalent to [A-Za-z0-9_].

\W Matches any nonword character. Equivalent to [^A-Za-z0-9_].
\num Matches num, where num is a positive integer. A reference back to remember
ed matches. \1 matches what is stored in RegExp.$1.
/n/ Matches n, where n is an octal, hexadecimal, or decimal escape value. Allow
s embedding of ASCII codes into regular expressions.

[zigzag]

用typeOf()函数。
if(typeOf(x)=="number")
{
do sth....
}