{
if (!IsPostBack)
{
PopulateTreeView()
}
}
//从数据库中获得数据并创建第一级treeview items
private void PopulateTreeView()
{
DataTable treeViewData = getTreeViewDate()
AddTopTreeViewNodes(treeViewData)
}
//使用dataAdapter he dataTable 处理数据库数据
private DataTable getTreeViewDate()
{
return ProductTypeManager.getAll()
}
//过滤数据 获得parentid为null的项
private void AddTopTreeViewNodes(DataTable treeViewDate)
{
DataView view = new DataView(treeViewDate)
view.RowFilter = "ParentId is null"
foreach (DataRowView row in view)
{
TreeNode newNode = new TreeNode(row["typeName"].ToString(), row["id"].ToString())
tvType.Nodes.Add(newNode)
AddChildTreeViewNodes(treeViewDate, newNode)
}
}
//添加子项
private void AddChildTreeViewNodes(DataTable treeVIewData, TreeNode parentTreeViewNode)
{
DataView view = new DataView(treeVIewData)
view.RowFilter = "parentid=" + parentTreeViewNode.Value
foreach (DataRowView row in view)
{
TreeNode newNode = new TreeNode(row["typeName"].ToString(), row["id"].ToString())
parentTreeViewNode.ChildNodes.Add(newNode)
AddChildTreeViewNodes(treeVIewData, newNode)
}
}
1、准备表结构及对应的表数据a、表结构:
create table TB_TREE
(
CID NUMBER not null,
CNAME VARCHAR2(50),
PID NUMBER //父节点
)
b、表数据:
insert into tb_tree (CID, CNAME, PID) values (1, '中国', 0)
insert into tb_tree (CID, CNAME, PID) values (2, '北京市', 1)
insert into tb_tree (CID, CNAME, PID) values (3, '广东省', 1)
insert into tb_tree (CID, CNAME, PID) values (4, '上海市', 1)
insert into tb_tree (CID, CNAME, PID) values (5, '广州市', 3)
insert into tb_tree (CID, CNAME, PID) values (6, '深圳市', 3)
insert into tb_tree (CID, CNAME, PID) values (7, '海珠区', 5)
insert into tb_tree (CID, CNAME, PID) values (8, '天河区', 5)
insert into tb_tree (CID, CNAME, PID) values (9, '福田区', 6)
insert into tb_tree (CID, CNAME, PID) values (10, '南山区', 6)
insert into tb_tree (CID, CNAME, PID) values (11, '密云县', 2)
insert into tb_tree (CID, CNAME, PID) values (12, '浦东', 4)
2、TreeNode对象,对应tb_tree
public class TreeNode implements Serializable {
private Integer cid
private String cname
private Integer pid
private List nodes = new ArrayList()
public TreeNode() {
}
//getter、setter省略
}
3、测试数据
public class TreeNodeTest {
@Test
public void loadTree() throws Exception{
System.out.println(JsonUtils.javaToJson(recursiveTree(1)))
}
/**
* 递归算法解析成树形结构
*
* @param cid
* @return
* @author jiqinlin
*/
public TreeNode recursiveTree(int cid) {
//根据cid获取节点对象(SELECT * FROM tb_tree t WHERE t.cid=?)
TreeNode node = personService.getreeNode(cid)
//查询cid下的所有子节点(SELECT * FROM tb_tree t WHERE t.pid=?)
List childTreeNodes = personService.queryTreeNode(cid)
//遍历子节点
for(TreeNode child : childTreeNodes){
TreeNode n = recursiveTree(child.getCid())//递归
node.getNodes().add(n)
}
return node
}
}
输出的json格式如下:
{
"cid": 1,
"nodes": [
{
"cid": 2,
"nodes": [
{
"cid": 11,
"nodes": [
],
"cname": "密云县",
"pid": 2
}
],
"cname": "北京市",
"pid": 1
},
{
"cid": 3,
"nodes": [
{
"cid": 5,
"nodes": [
{
"cid": 7,
"nodes": [
],
"cname": "海珠区",
"pid": 5
},
{
"cid": 8,
"nodes": [
],
"cname": "天河区",
"pid": 5
}
],
"cname": "广州市",
"pid": 3
},
{
"cid": 6,
"nodes": [
{
"cid": 9,
"nodes": [
],
"cname": "福田区",
"pid": 6
},
{
"cid": 10,
"nodes": [
],
"cname": "南山区",
"pid": 6
}
],
"cname": "深圳市",
"pid": 3
}
],
"cname": "广东省",
"pid": 1
},
{
"cid": 4,
"nodes": [
{
"cid": 12,
"nodes": [
],
"cname": "浦东",
"pid": 4
}
],
"cname": "上海市",
"pid": 1
}
],
"cname": "中国",
"pid": 0
}
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