C# 将数据库转换为实体数据模型。事实上，它也会使删除变得容易，当你删除一个边缘时，它可以自动从每个节点删除它。非常感谢你的所有回复，这当然给了我一些思考的东西。我想我会沿着Hightechrider建议的路线走，直到遇到一些问题。因此，我接受了他的回答。 pu

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将数据库转换为实体数据模型。事实上，它也会使删除变得容易，当你删除一个边缘时，它可以自动从每个节点删除它。非常感谢你的所有回复，这当然给了我一些思考的东西。我想我会沿着Hightechrider建议的路线走，直到遇到一些问题。因此，我接受了他的回答。

public class Node
{
    // Has Some Data!
}

public class Branch
{
    // Contains references to Nodes
    public Node NodeA
    public Node NodeB
}

public class Graph
{
    public List<Node> Nodes;
    public List<Branch> Branches;
}

class Branch
{
    public Branch(Node nodeA, Node nodeB) { NodeA = nodeA; NodeB = nodeB; }
    public Node NodeA { get; set; }
    public Node NodeB { get; set; }
}

class Node
{
    public Node(string name) { Name = name; }
    public string Name { get; set; }
}

List<Node> nodes = new List<Node>() { new Node("Apple"), new Node("Banana") };
List<Branch> branches = new List<Branch>() { new Branch(nodes[0], nodes[1]), new Branch(nodes[1], nodes[0]) };

Node node = nodes[0];
nodes.Remove(node);

var query = from branch in branches
            where branch.NodeA == node || branch.NodeB == node 
            select branch;

foreach (Branch branch in query)
{
    if (branch.NodeA == node)
        branch.NodeA = null;
    if (branch.NodeB == node) // could just be 'else' if NodeA cannot equal NodeB
        branch.NodeB = null;
}

public class Node
{
    // Has Some Data!

    public List<Branch> BranchesIn;
    public List<Branch> BranchesOut;  // assuming this is a directed graph

    public void Delete()
    {
      foreach (var branch in BranchesIn)
        branch.NodeB.BranchesOut.Remove(branch);

      foreach (var branch in BranchesOut)
        branch.NodeA.BranchesIn.Remove(branch);

      BranchesIn.Clear();
      BranchesOut.Clear();
     }
}

public class Branch
{
    // Contains references to Nodes
    public Node NodeA
    public Node NodeB
}