jQuery - unrecognized expression: :nth-child

Question

I am trying to select `:nth-child` using jquery, but it show syntax error. ``` Error: Syntax error, unrecognized expression: :nth-child ``` Here is my code ``` var i; jQuery('#' + id + ' .tab-pane').each(function (id, t) { var n = jQuery(this).attr('id', 'pane-' + t); var p_id = n.attr('id'); jQuery('#' + id + ' .nav-tabs li:nth-child(' + i + ') a').attr('href', p_id); i++; }); ``` please check my code what is missing here

Accepted Answer

On the first iteration, there is no value for `i`. So the query looks like this:

```
jQuery('#' + id + ' .nav-tabs li:nth-child(undefined) a').attr('href', p_id);
```

On following iterations, it will be `undefined++`, which is `NaN`, which still won't work.

This obviously won't work. The solution is to set `i` to `1` (or to whatever value is necesary) on the first loop:

```
var i = 1;
```

jQuery - unrecognized expression: :nth-child

Solution

Problem