在这种情况下如何使用正则表达式？

Question

I have got a variable as 30_KK_1_KK_2

How can i get the value after first KK_ and second KK_ ?

so that the output for First KK_ is 1 and

for the second KK_ it is 2

I have tried it this way

var str =  "30_KK_1_KK_2";
var n[] = str.split('_KK_');
alert(n[0]);
alert(n[1]);

Answer 1

You have several typos.

1) No string quotes around the string constant

2) var n[] is not valid... simply var n

3) You need to get elements 1 and 2 as element 0 is "30"

var str =  "30_KK_1_KK_2";
var n = str.split('_KK_');
alert(n[1]);
alert(n[2]);

JSFiddle: http://jsfiddle.net/TrueBlueAussie/w3mLgowc/1/

A regular expression is probably overkill for such a simple problem (and the delimiter is fixed).

Answer 2

If you want to really use Regex you can try this code :

var str =  "30_KK_1_KK_2";
regex = /.*KK_(\d*)_KK_(\d*)/g;
value_1 = str.replace(regex,"$1");
value_2 = str.replace(regex,"$2");
alert(value_1);
alert(value_2);