www.pudn.com > TreeView_Sample.rar > TreeFillThrd.pas

unit TreeFillThrd; 
 
interface 
 
uses 
  Classes, ComCtrls, ADODB, SysUtils; 
 
type 
  TNodeData = record 
    Index: integer; 
    Caption: string; 
  end; 
  PNodeData = ^TNodeData; 
  TTreeFill = class(TThread) 
    TV: TTreeView; 
    TableName: string; 
    FieldIndex: string; 
    FieldPID: string; 
    FieldCaption: string; 
    RootText: string; 
    Conn: TADOConnection; 
    Ptr: PNodeData; 
    constructor Create(ATreeView: TTreeView; AConn: TADOConnection; 
      ATable: string; ARootText: string = '我的目录'; 
      AFieldIndex: string = 'ID'; AFieldPID: string = 'PID'; 
      AFieldCaption: string = 'Caption'); 
  private 
    procedure AddTree(Node: TTreeNode; PN: PNodeData); 
  protected 
    procedure Execute; override; 
  end; 
 
implementation 
//------------------------------------------------------------------------------ 
constructor TTreeFill.Create(ATreeView: TTreeView; AConn: TADOConnection; 
  ATable: string; ARootText: string = '我的目录'; 
  AFieldIndex: string = 'ID'; AFieldPID: string = 'PID'; 
  AFieldCaption: string = 'Caption'); 
begin 
  FieldIndex := AFieldIndex; 
  FieldPID := AFieldPID; 
  FieldCaption := AFieldCaption; 
  TV := ATreeView; 
  TableName := ATable; 
  RootText := ARootText; 
  Conn := AConn; 
  New(Ptr); 
  inherited Create(False); 
end; 
//------------------------------------------------------------------------------ 
procedure TTreeFill.Execute; 
var 
  Node: TTreeNode; 
begin 
  FreeOnTerminate := True; 
  TV.Items.Clear; 
  Ptr^.Index := 0; 
  Ptr^.Caption := RootText; 
  Node := TV.Items.AddObject(nil, RootText, Ptr); 
  Node.ImageIndex := 0; 
  Node.SelectedIndex := 0; 
  AddTree(Node, Ptr); 
  TV.FullExpand; 
end; 
//------------------------------------------------------------------------------ 
procedure TTreeFill.AddTree(Node: TTreeNode; PN: PNodeData); 
var Query: TADOQuery; 
  nNode: TTreeNode; 
  PNode: PNodeData; 
begin 
  try 
    Query := TADOQuery.Create(nil); 
    Query.Connection := Conn; 
    Query.SQL.Text := 'Select * from ' + TableName + ' where ' + FieldPID + ' =' + IntToStr(PN^.Index); 
    if Query.Active then 
      Query.Close; 
    Query.Open; 
    while Query.Eof = False do 
    begin 
      New(PNode); 
      PNode^.Caption := Query.FieldByName(FieldCaption).AsString; 
      PNode^.Index := Query.FieldByName(FieldIndex).AsInteger; 
      nNode := TV.Items.AddChildObject(Node, PNode^.Caption, PNode); 
      nNode.ImageIndex := 1; 
      nNode.SelectedIndex := 2; 
      AddTree(nNode, PNode); 
      Query.Next; 
    end; 
  finally 
    Query.Free; 
  end; 
end; 
//------------------------------------------------------------------------------ 
end.