Error in IE9.0.12

Getting an error that match value is null or can't be found. added this to get rid of it:

var oPercent;
        if ($(this).attr('style') != null) {
            oPercent = $(this).attr('style').match(/margin-left:(.*[0-9])/i) && parseInt(RegExp.$1);

```
    }
    return oPercent;
```

Any issues with this above?
