Move-Methode (Beispiel) (VJ++)

Gilt für: Access 2013, Office 2013

In diesem Beispiel wird die Move-Methode verwendet, um den Zeiger für den Datensatz auf der Grundlage der Benutzereingabe zu positionieren.

 
// BeginMoveJ 
import java.io.*; 
import com.ms.wfc.data.*; 
import com.ms.com.*; 
 
public class MoveX 
{ 
 // The main entry point for the application. 
 
 public static void main (String[] args) 
 { 
 MoveX(); 
 System.exit(0); 
 } 
 // MoveX Function 
 
 static void MoveX() 
 { 
 // Define ADO Objects 
 Recordset rstAuthors = null; 
 
 // Declarations 
 String line = null; 
 Variant varBookmark; 
 String strCommand = null; 
 int lngMove; 
 BufferedReader in = 
 new BufferedReader(new InputStreamReader(System.in)); 
 
 try 
 { 
 // Open recordset from Authors table. 
 String strCnn = "Provider='sqloledb';Data Source='MySqlServer';"+ 
 "Initial Catalog='Pubs';Integrated Security='SSPI';"; 
 
 rstAuthors = new Recordset(); 
 rstAuthors.setCursorType(AdoEnums.CursorType.STATIC); 
 
 // Use client cursor to allow use of 
 // Absolute Position property. 
 rstAuthors.setCursorLocation(AdoEnums.CursorLocation.CLIENT); 
 rstAuthors.open("select au_id,au_fname,au_lname,city,state " + 
 "from Authors order by au_lname", 
 strCnn,AdoEnums.CursorType.STATIC, 
 AdoEnums.CursorLocation.CLIENT, AdoEnums.CommandType.TEXT); 
 
 rstAuthors.moveFirst(); 
 
 while(true) 
 { 
 // Display information about current record and 
 // ask how many records to move. 
 strCommand = "Record:\t\t"+ rstAuthors.getAbsolutePosition() + 
 " of " + rstAuthors.getRecordCount() + "\n" + "\tAuthor:\t\t" 
 + rstAuthors.getField("au_fname").getString() + 
 " " + rstAuthors.getField("au_lname").getString() + 
 "\n" +"\tLocation:\t" + 
 rstAuthors.getField("city").getString() + 
 ", " +rstAuthors.getField("state").getString() 
 +"\n\n"+"\tEnter number of records to move" + 
 " (positive or negative)."; 
 
 System.out.print("\t"+ strCommand + "\t"); 
 line =in.readLine(); 
 
 // No entry exits program loop. 
 if (line.length()== 0) 
 break; 
 
 // Converts string entry to int. 
 lngMove = Integer.parseInt(line); 
 
 // Store bookmark in case the move goes too far 
 // forward or backward. 
 varBookmark =(Variant)rstAuthors.getBookmark(); 
 
 // Move method requires parameter of data type int. 
 rstAuthors.move(lngMove); 
 
 // Trap for BOF and EOF. 
 if (rstAuthors.getBOF()) 
 { 
 System.out.println("\tToo far backward! " + 
 "Returning to the current record."); 
 rstAuthors.setBookmark(varBookmark); 
 } 
 if (rstAuthors.getEOF()) 
 { 
 System.out.println("\tToo far forward! " + 
 "Returning to the current record."); 
 rstAuthors.setBookmark(varBookmark); 
 } 
 } 
 System.out.println("\tPress <Enter> to continue.."); 
 in.readLine(); 
 } 
 
 catch(AdoException ae) 
 { 
 // Notify user of any errors that result from ADO. 
 
 // As passing a recordset, check for null pointer. 
 if (rstAuthors!=null) 
 { 
 PrintProviderError(rstAuthors.getActiveConnection()); 
 } 
 else 
 { 
 System.out.println(" Exception: "+ ae.getMessage()); 
 } 
 } 
 // System Read requires this catch. 
 catch(java.io.IOException je) 
 { 
 PrintIOError(je); 
 } 
 // Required if the user enter non integer value. 
 catch(java.lang.NumberFormatException ne) 
 { 
 System.out.println("\n\nPlease enter integer values!"); 
 rstAuthors.close(); 
 } 
 
 finally 
 { 
 // Cleanup objects before exit. 
 if (rstAuthors != null) 
 if (rstAuthors.getState() == 1) 
 rstAuthors.close(); 
 } 
 } 
 // PrintProviderError Function 
 
 static void PrintProviderError( Connection Cnn1 ) 
 { 
 // Print Provider errors from Connection object. 
 // ErrItem is an item object in the Connections Errors collection. 
 com.ms.wfc.data.Error ErrItem = null; 
 long nCount = 0; 
 int i = 0; 
 
 nCount = Cnn1.getErrors().getCount(); 
 
 // If there are any errors in the collection, print them. 
 if( nCount > 0); 
 { 
 // Collection ranges from 0 to nCount - 1 
 for (i = 0; i< nCount; i++) 
 { 
 ErrItem = Cnn1.getErrors().getItem(i); 
 System.out.println("\t Error number: " + ErrItem.getNumber() 
 + "\t" + ErrItem.getDescription() ); 
 } 
 } 
 
 } 
 
 // PrintIOError Function 
 
 static void PrintIOError( java.io.IOException je) 
 { 
 System.out.println("Error \n"); 
 System.out.println("\tSource = " + je.getClass() + "\n"); 
 System.out.println("\tDescription = " + je.getMessage() + "\n"); 
 } 
} 
// EndMoveJ