I am wondering to how to get number from an array. I have tried its give me NaN error
<script type="text/javascript">
$(function(){
var Arr = [ 'h78em', 'w145px', 'w13px' ]
alert(parseInt(Arr[0]))
})
</script>
7 Answers
try with
+Arr[0].replace(/\D/g, '');
Example fiddle: http://jsfiddle.net/t6yCV/
Starting + is working like parseInt() and it is necessary if you need to perform some mathematical operation with the number obtained: in fact
typeof Arr[0].replace(/\D/g,'') // String
typeof +Arr[0].replace(/\D/g,'') // Number
answered Aug 30, 2012 at 8:06
Fabrizio Calderan
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Comments
Try:
['h78em', 'w145px', 'w13px']
.map(function(a){return ~~(a.replace(/\D/g,''));});
//=> [78, 145, 13]
Or use a somewhat more elaborate String prototype extension:
String.prototype.intsFromString = function(combine){
var nums = this.match(/\d{1,}/g);
return !nums ? 0
: nums.length>1 ? combine ? ~~nums.join('')
: nums.map(function(a){return ~~a;})
: ~~nums[0];
};
// usage
'abc23'.intsFromString(); //=> 23
'3abc121cde'.intsFromString(); //=> [3,121]
'3abc121cde'.intsFromString(true); //=> 3121
'abcde'.intsFromString(); //=> 0
// and ofcourse
['h78em', 'w145px', 'w13px'].map(function(a){return a.intsFromString();});
//=> [78, 145, 13]
2 Comments
Fabrizio Calderan
Nice: just for simplification:
[^\d] ==> \D - and unfortunately IE8 doesn't support map
KooiInc
@Fabrizio: yep, adjusted. You can find a
Array.prototype.map shim @ developer.mozilla.org/en-US/docs/JavaScript/Reference/…You can build a function that builds the number from your string:
function stringToNum(str){
num = 0;
for (i = 0; i < str.length; i++)
if (str[i] >= '0' && str[i] <= '9')
num = num * 10 + parseInt(str[i]);
return num;
}
jsFiddle : http://jsfiddle.net/8WwHh/
4 Comments
Jitender
Wow!, Can you please tell what is the logic behind it
gabitzish
you start with num = 0, and iterate the characters from the string. If you find a digit, you multiply your number with 10 and add the new digit at the end.
KooiInc
What to do with
stringToNum('123abc345def')?KooiInc
It depends: would you like to see the values as separate numbers, or as a single number? The latter case is what your method covers, but for the first case your method wouldn't be sufficient.
Try this:
var Arr = [ 'h78em', 'w145px', 'w13px' ]
function stringToNum(str){
return str.match(/\d+/g);
}
alert(stringToNum(Arr[0]));
answered Aug 30, 2012 at 11:23
Dhanasekar Murugesan
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Comments
Yet another quick and dirty solution:
alert(Arr[0].match("\\d+"));
Comments
1 Comment
Flater
Mind for case sensitiveness. Also, this would make something like "a52eb2" in 522. Not sure if that is correct, you might end up with a different number.
h78emis not a number.parseInt(Arr[0].replace(/\D/g), ''). Do you care about more complex cases likeabc123def456?