try and catch does not handle the exception in the iphone


i am using the following code to catch an error when ind.row is not a valid value or sometimes it becomes nil

@try {
        if(ind.row<[[treeNode flattenElements] count])
            [self.mTableView scrollToRowAtIndexPath:ind atScrollPosition:UITableViewScrollPositionTop animated:YES];

    @catch (NSException *e) {


but when this code executes sometimes this error is occuring

Assertion failure in -[NSIndexPath row], /SourceCache/UIKit_Sim/UIKit-1262.60.3/UITableViewSupport.m:1948`

what may be the reason for this error and why exception is not being handled

Assertions in iOS don't throw exceptions, so you can't catch them.

You are going to need to figure out what's wrong with your call to -row. My first guess would be that "ind" is already freed or something.