開發工具以及開發語言:Visual Studio.net 2005 C#

數據庫:SQL Server 2000

數據庫名:IELKQ 密碼為空

向里面添加如下數據(注,其中的部門名稱是我亂來的)

解釋:DEPT_ID是部門號,NAME_DEP是部門名稱,ID_DEPT是所屬的部門號,其意義是,如:DEPT_ID 為000000 NAME_DEP為北京檢查院,ID_DEPT為000000表示這是根節點,也就是一級節點,又如:DEPT_ID為000004,NAME_DEP為成都檢查院,ID_DEPT為000004也是指這是根節點,也是一級節點,又如DEPT_ID為000002,NAME_DEP為檢查辦,ID_DEPT為000000,表示這個部門是北京檢查院的下級部門,也就是二級節點,DEPT_ID為000003這個部門是DEPT_ID為000001的子部門,是它的更下一級節點,

需要的控件不多,一個TreeView控件,其dock屬性設置為fill,然后一個Button,其text屬性設置為"分類"

大概思路是這樣的:現把一級節點(根節點)找出來,也就是DEPT_ID和ID_DEPT相同的記錄,然后再用DEPT_ID去找和ID_DEPT相同的記錄,那么這些記錄就是二級節點,在AddNote(...)函數中把這些二級節點的記錄記錄在一張新表中(這就是為什么要不斷創建新表的原因),并用foreach循環添加這些二級節點,循環中使用遞歸,這樣就不斷的添加三級節點,四季節點等等節點這樣功能就實現了

using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Text; using System.Windows.Forms; using System.Collections; using System.Data.SqlClient; namespace 無限級分類樹 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private string strCon = "server=(local);uid=sa;pwd=;database=IELKQ"; private DataTable DT; private string AddNote(DataTable DT1,string id,TreeNode node) { DataTable dt1; dt1 = new DataTable(); DataColumn dc = new DataColumn(); dc.ColumnName = "DEPT_ID"; DataColumn dc1 = new DataColumn(); dc1.ColumnName = "ID_DEPT"; DataColumn dc2 = new DataColumn(); dc2.ColumnName = "NAME_DEP"; dt1.Columns.Add(dc); dt1.Columns.Add(dc1); dt1.Columns.Add(dc2); foreach (DataRow DR in DT1.Rows) { if (id != DR.ItemArray[0].ToString() && id == DR.ItemArray[1].ToString()) { DataRow dr = dt1.NewRow(); dr["DEPT_ID"] = DR.ItemArray[0].ToString(); dr["ID_DEPT"] = DR.ItemArray[1].ToString(); dr["NAME_DEP"] = DR.ItemArray[2].ToString(); dt1.Rows.Add(dr); } } //創建新表 foreach (DataRow dr1 in dt1.Rows) { TreeNode nodes = new TreeNode(); nodes.Text = dr1.ItemArray[2].ToString(); node.Nodes.Add(nodes); AddNote(DT, dr1.ItemArray[0].ToString(), nodes); } return ""; } private void button1_Click(object sender, EventArgs e) { this.treeView1.Nodes.Clear(); SqlConnection Con = new SqlConnection(strCon); Con.Open(); SqlCommand Com = new SqlCommand(); Com.CommandText = "select DEPT_ID,ID_DEPT,NAME_DEP from DEPT"; Com.Connection = Con; SqlDataAdapter adp = new SqlDataAdapter(); adp.SelectCommand = Com; DataSet DS = new DataSet(); adp.Fill(DS); DT = DS.Tables[0]; ArrayList al = new ArrayList(); ArrayList al1=new ArrayList(); foreach (DataRow dr in DT.Rows) { if (dr.ItemArray[0].ToString() == dr.ItemArray[1].ToString()) { al.Add(dr.ItemArray[0].ToString()); al1.Add(dr.ItemArray[2].ToString()); } } for (int i = 0; i < al.Count; i++) { TreeNode nod=new TreeNode(); nod.Text=al1[i].ToString(); this.treeView1.Nodes.Add(nod); AddNote(DT, al[i].ToString(), nod); } Con.Close(); } private void treeView1_Click(object sender, EventArgs e) { } } }

(C#)實現無限級分類樹