NSMutableArray使用過程出現問題

代碼：

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath

{

    // Navigation logic may go here. Create and push another view controller.

    /*

     <#DetailViewController#> *detailViewController = [[<#DetailViewController#> alloc] initWithNibName:@"<#Nib name#>" bundle:nil];

     // ...

     // Pass the selected object to the new view controller.

     [self.navigationController pushViewController:detailViewController animated:YES];

     [detailViewController release];

     */

    

    NSLog( @"%@" , indexPath );

    NSLog(
@"%@" , datesMutableArray_ );

    NSLog(
@"dateMutableArray_ %@" , dateMutableArray_ );

    

    id date = [ datesMutableArray_
objectAtIndex: indexPath.section ];

//    id date = [ dateMutableArray_ objectAtIndex: indexPath.section ];

／／——————————————————————————————————————————————————————————————————————————

數組 dateMutableArray_   與數組 datesMutableArray_ 存放的內容一樣，只是

dateMutableArray_ = [ NSArray
arrayWithArray: datesMutableArray_ ];

當其進入到以上函數時就出現錯誤：數組 dateMutableArray_出現問題