過濾數據表並將其保存到另一個數據表

Question

需要一些工作測試示例，我試過其他選項，但似乎不工作。

請看附圖。

Answer 1

您需要一個遞歸樹結構。

using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using System.Data; 

namespace ConsoleApplication1 
{ 
    class Program 
    { 
     static void Main(string[] args) 
     { 
      FolderTree tree = new FolderTree(); 
      tree.BuildTree(); 
     } 
    } 
    public class FolderTree 
    { 
     public static FolderTree root { get; set; } 

     public int id { get; set; } 
     public List<FolderTree> children { get; set; } 

     static DataTable dt { get; set; } 

     public void BuildTree() 
     { 
      dt = new DataTable(); 
      dt.Columns.Add("FolderID", typeof(int)); 
      dt.Columns.Add("PARENT_ID", typeof(int)); 

      dt.Rows.Add(new object[] { 1, 0 }); 
      dt.Rows.Add(new object[] { 2, 0 }); 
      dt.Rows.Add(new object[] { 3, 2 }); 
      dt.Rows.Add(new object[] { 4, 1 }); 
      dt.Rows.Add(new object[] { 5, 0 }); 
      dt.Rows.Add(new object[] { 6, 4 }); 
      dt.Rows.Add(new object[] { 7, 3 }); 
      dt.Rows.Add(new object[] { 8, 0 }); 
      dt.Rows.Add(new object[] { 9, 1 }); 
      dt.Rows.Add(new object[] { 10, 8 }); 
      dt.Rows.Add(new object[] { 11, 0 }); 
      dt.Rows.Add(new object[] { 12, 11 }); 
      dt.Rows.Add(new object[] { 13, 0 }); 
      dt.Rows.Add(new object[] { 14, 0 }); 
      dt.Rows.Add(new object[] { 15, 2 }); 

      root = new FolderTree(); 
      BuildTreeRecursive(0, root); 
     } 
     void BuildTreeRecursive(int parentID, FolderTree parent) 
     { 
      parent.id = parentID; 
      foreach(DataRow folder in dt.AsEnumerable().Where(x => x.Field<int>("PARENT_ID") == parentID)) 
      { 
       if (parent.children == null) 
       { 
        parent.children = new List<FolderTree>(); 
       } 
       FolderTree child = new FolderTree(); 
       int childID = folder.Field<int>("FolderID"); 
       parent.children.Add(child); 
       BuildTreeRecursive(childID, child); 
      } 
     } 
    } 
}