用数据表创建树_delphi教程

数据库结构:
字段 类型
ID 整型 索引(无重复)
name 文本
father 整型

//tree初始化
procedure TForm1.FormActivate(Sender: TObject);
var i:integer;
begin
treeview1.Items.BeginUpdate;
while not(adotable1.Eof) do
begin
if ADOTable1.FieldValues[father]=0 then
treeview1.Items.addchild(treeview1.DropTarget,ADOTable1.FieldValues[name])
else
begin
i:=0;
repeat
if treeview1.Items.Item[i].Text = ADOTable1.Lookup(ID,ADOTable1.FieldValues[father],name) then
begin
treeview1.Items.AddChild(treeview1.Items.Item[i],ADOTable1.FieldValues[name]);
break;
end;
i:=i+1;
until i>adotable1.RecordCount;
end;
ADOTable1.next;
end;
treeview1.Items.EndUpdate;
end;

//tree添加
procedure TForm1.Button1Click(Sender: TObject);
var i:integer;
begin
adotable1.Last;
i:=adotable1.FieldValues[ID];
if checkbox1.Checked=false then
begin
adotable1.InsertRecord([edit1.Text,adotable1.Lookup(name,treeview1.Selected.Text,ID),i+1]);
treeview1.Items.AddChild(treeview1.Selected,edit1.Text);
end
else
begin
adotable1.InsertRecord([edit1.Text,0,i+1]);
treeview1.Items.AddChild(treeview1.DropTarget,edit1.Text);
end;
end;

//tree删除
procedure TForm1.Button3Click(Sender: TObject);
begin
if treeview1.Selected.HasChildren then
begin
showmessage(含有子项,不能删除.);
abort;
end;
begin
adotable1.Locate(name,treeview1.Selected.Text,[loPartialKey]);
adotable1.Delete;
treeview1.Items.Delete(treeview1.Selected);
end;
end;

//tree图标
procedure TForm1.TreeView1GetImageIndex(Sender: TObject; Node: TTreeNode);
begin
if Node.Expanded then
Node.ImageIndex := 1
else
Node.ImageIndex := 0
end;

//tree图标
procedure TForm1.TreeView1GetSelectedIndex(Sender: TObject;Node: TTreeNode);
begin
node.SelectedIndex:=node.ImageIndex;
end;

//list初始化
procedure TForm1.TreeView1MouseDown(Sender: TObject; Button: TMouseButton;Shift: TShiftState; X, Y: Integer);
var p:pointer;
begin
listview1.Items.Clear;
if adotable2.Locate(class,adotable1.Lookup(name,treeview1.Selected.Text,ID),[loPartialKey])=true then
begin
p:=listview1.Items.Add;
listview1.Items.Item[listview1.Items.IndexOf(p)].Caption:=adotable2.FieldValues[name];
listview1.Items.Item[listview1.Items.IndexOf(p)].SubItems.Add(adotable2.FieldValues[url]);
end;
end;

//list添加
procedure TForm1.Button2Click(Sender: TObject);
var p:pointer;
begin
p:=listview1.Items.Add;
listview1.Items.Item[listview1.Items.IndexOf(p)].Caption:=edit2.Text;
listview1.Items.Item[listview1.Items.IndexOf(p)].SubItems.Add(edit3.Text);
adotable2.InsertRecord([adotable1.Lookup(name,treeview1.Selected.Text,ID),edit2.Text,edit3.Text]);
end;

//list删除
procedure TForm1.Button4Click(Sender: TObject);
begin
adotable2.Locate(name,listview1.Selected.Caption,[loPartialKey]);
adotable2.Delete;
listview1.Selected.Delete;
end;

posted @   麦麦提敏  阅读(541)  评论(0编辑  收藏  举报
(评论功能已被禁用)
编辑推荐:
· AI与.NET技术实操系列:向量存储与相似性搜索在 .NET 中的实现
· 基于Microsoft.Extensions.AI核心库实现RAG应用
· Linux系列:如何用heaptrack跟踪.NET程序的非托管内存泄露
· 开发者必知的日志记录最佳实践
· SQL Server 2025 AI相关能力初探
阅读排行:
· winform 绘制太阳,地球,月球 运作规律
· 震惊!C++程序真的从main开始吗?99%的程序员都答错了
· AI与.NET技术实操系列(五):向量存储与相似性搜索在 .NET 中的实现
· 【硬核科普】Trae如何「偷看」你的代码?零基础破解AI编程运行原理
· 超详细:普通电脑也行Windows部署deepseek R1训练数据并当服务器共享给他人
点击右上角即可分享
微信分享提示