dbiisrecordlocked.html

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Checks the lock status of the current record.
<hr size=2 noshade>

This example uses the following input:<BR>
<I>IsRecordLocked(Table1, True);</I><BR>
NOTE: If ByAnyone is true, then the function also checks if 
any other session has the record locked. If ByAnyone is false, then
only the current session is checked. The function returns False if 
not locked, and True if locked.

<PRE>function IsRecordLocked(Table: TTable; ByAnyone: boolean): boolean;
var
  Locked: BOOL;
  hCur: hDBICur;
  rslt: DBIResult;

begin
  Table.UpdateCursorPos;
  // Is the record locked by the current session...
  Check(DbiIsRecordLocked(Table.Handle, Locked));
  Result := Locked;
  // If the current session does not have a lock and the ByAnyone varable is
  // set to check all sessions, continue check...
  if (Result = False) and (ByAnyone = True) then
  begin
    // Get a new cursor to the same record...
    Check(DbiCloneCursor(Table.Handle, False, False, hCur));
    try
      // Try and get the record with a write lock...
      rslt := DbiGetRecord(hCur, dbiWRITELOCK, nil, nil);
      if rslt <> DBIERR_NONE then
      begin
        // if an error occured and it is a lock error, return true...
        if HiByte(rslt) = ERRCAT_LOCKCONFLICT then
          Result := True
        else
          // If some other error happened, throw an exception...
          Check(rslt);
      end
      else
        // Release the lock in this session if the function was successful...
        Check(DbiRelRecordLock(hCur, False));
    finally
      // Close the cloned cursor...
      Check(DbiCloseCursor(hCur));
    end;
  end;
end;</PRE>
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