File open dialog

Use the following code

x_fext = 'TXT

  CALL METHOD cl_gui_frontend_services=>file_open_dialog
    EXPORTING
      window_title            = c_title
      default_extension       = c_fext
    default_filename        = 'file.txt'
*    FILE_FILTER             =
     initial_directory       = 'c:'
       multiselection          = abap_false
*    WITH_ENCODING           =
    CHANGING
      file_table              = li_file
      rc                      = sy-subrc
*    USER_ACTION             =
*    FILE_ENCODING           =
    EXCEPTIONS
      file_open_dialog_failed = 1
      cntl_error              = 2
      error_no_gui            = 3
      not_supported_by_gui    = 4
      OTHERS                  = 5

dump :

Runtime errors         MESSAGE_TYPE_X                                       
       Occurred on     22.03.2006 at   12:04:25                                                                                
The current application triggered a termination with a short dump.                                                                                
What happened?                                                                                
The current application program detected a situation which really           
should not occur. Therefore, a termination with a short dump was            
triggered on purpose by the key word MESSAGE (type X).                                                                                
What can you do?                                                                                
Print out the error message (using the "Print" function)                    
and make a note of the actions and input that caused the                    
error.                                                                                
To resolve the problem, contact your SAP system administrator.              
You can use transaction ST22 (ABAP Dump Analysis) to view and administer    
 termination messages, especially those beyond their normal deletion        
date.                                                                                
Error analysis                                                                                
Short text of error message:                                                
Error number 1 receiving the results of an OLE call                                                                                
Technical information about the message:                                    
 Diagnosis                                                                  
     The system could not assign the results of an OLE Automation call t    
     Meanings of the error number " "                                       
     o   -1: The event memory of the automation queue is destroyed - int    
     o    1: There is no valid link to the program variables (PcbInvalid    
     o    2: The link cannot be expanded (PcbInternal)                      
     o    3: The link points to an internal table that has been cleared     
     o   4: The link points to a local variable whose stack frame has be    
     Note: Errors 3 and 4 indicate a programming error. When you program    
     the return value (for example, the selected node of a tree) is not     
     reasons, control calls are not necessarily sent to the front end im    
     instead. The queue may be sent to the frontend at a point where the    
     for example, the call occurred in a subroutine that had ended by th    
     control calls with local importing parameters.