Javascript中如何递增替换其中的几个数字

Question

为了实现girdview中的上下控件的跳转
需要实现替换这个id中的几个字母
例如：ctl00_ContentPlaceHolder1_GridView1_ctl03_txtMonth9中
将“_ctl03_” 替换为“_ctl02_” 或者 “_ctl04_” 
有没有简单的正则表达实现？
谢谢

Answer 1

<script type="text/javascript">
str="ctl00_ContentPlaceHolder1_GridView1_ctl03_txtMonth9";
alert(str.replace("_ct103_","_ct102_"));//把ct102换为104为替换元素
</script>

Answer 2

var reg4=new RegExp("(ctl00_ContentPlaceHolder1_GridView1_)(\\w+)(_txtMonth9)")
var str="ctl00_ContentPlaceHolder1_GridView1_ctl03_txtMonth9";
reg4.test(str);alert(RegExp.$1);
alert(RegExp.$2);
alert(RegExp.$3);str=str.replace(RegExp.$2,"ctl02");
alert(str);

Answer 3

function inc(s) {
return s.replace(/_ctl(\d+)_/g, function($0, $1) {
return  ("00000" + ($1-0+1)).slice(-$1.length);
});
}function dec(s) {
return s.replace(/_ctl(\d+)_/g, function($0, $1) {
return  ("00000" + ($1-1)).slice(-$1.length);
});
}alert(dec('ctl00_ContentPlaceHolder1_GridView1_ctl03_txtMonth9'));
alert(inc('ctl00_ContentPlaceHolder1_GridView1_ctl03_txtMonth9'));