ios - 异常“发送到不可变对象的变异方法”

Question

我在下面方法的行中有一个异常，[array removeObjectsInArray:toRemove];无法理解它有什么问题..

- (void) handleDearchForTerm:(NSString *)searchTerm
{
    NSMutableArray *sectionsToRemove = [[NSMutableArray alloc] init];
    [self resetSearch];
    for (NSString *key in _keys)
    {
        NSMutableArray *array = [_names valueForKey:key];
        NSMutableArray *toRemove = [[NSMutableArray alloc] init];
        for (NSString *name in array)
        {
            if ([name rangeOfString:searchTerm options:NSCaseInsensitiveSearch].location == NSNotFound)
                [toRemove addObject:name];
        }
        if ([array count] == [toRemove count])
            [sectionsToRemove addObject:key];
        [array removeObjectsInArray:toRemove];
    }
    [_keys removeObjectsInArray:sectionsToRemove];
    [_table reloadData];
}

Answer 1

可能数组只是一个实例NSArray，但不是NSMutableArray，你应该检查_names setObject:forKeys:

Answer 2

改变：

 NSMutableArray *array = [_names valueForKey:key];

至：

 NSMutableArray *array = [[NSMutableArray alloc] initWithArray:[_names valueForKey:key]];

或者：

 NSMutableArray *array = [[_names valueForKey:key] mutableCopy];