UdpClient.receive crashes unity

Question

Been toying around with networking and I created a simple console application that can send messages over the internet but every time I've tried to bring what I made in my application always crashes unity.

 using System.Collections;
 using System.Collections.Generic;
 using System;
 using System.Net;
 using System.Net.Sockets;
 using System.IO;
 using System.Text;
 using UnityEngine;
 
 public class networkHost : MonoBehaviour
 {
     public int port;
     public IPEndPoint ipep;
     public IPEndPoint sender;
     public UdpClient newSock;
 
     byte[] receiveData;
 
     void Start()
     {
         receiveData = new byte[1024];
 
         ipep = new IPEndPoint(IPAddress.Any, port);
         newSock = new UdpClient(ipep);
         sender = new IPEndPoint(IPAddress.Any, 0);
     }
 
     void Update()
     {
         if (Input.GetKeyDown("j"))
         {
             ReceiveData();
         }
     }
 
     public void ReceiveData()
     {
         //This line crashes unity
         receiveData = newSock.Receive(ref sender);
 
         if (Encoding.ASCII.GetString(receiveData, 0, receiveData.Length) == "jump")
         {
             Jump(100);
         }
     }
 
     public void Jump(int force)
     {
         GetComponent<Rigidbody>().AddForce(Vector3.up * force);
     }
 }

I really don't know why it crashes, especially because it exists and works almost identically in a console application. Some help would be appreciated the next thing I was gonna look at was threading but I really don't know.

Answer 1

Figured it out did more reading, udpclient.receive blocks until it receives a datagram which in unity's case means it crashes, so I put it inside an if check, that works. This is what I have now.

 public class networkHost : MonoBehaviour
 {
     public string ip;
     public IPAddress hostaddress;
 
     public int port;
     public IPEndPoint ipep;
     public IPEndPoint sender;
     public UdpClient newSock;
     public Thread networkThread;
 
     public byte[] receivedData;
     public string dataString;
 
 
     void Start()
     {
         networkThread = new Thread(ReceiveData);
         networkThread.Start();
 
         receivedData = new byte[0];
 
         ipep = new IPEndPoint(IPAddress.Any, port);
         newSock = new UdpClient(ipep);
         sender = new IPEndPoint(IPAddress.Any, 0);
     }
 
     void Update()
     {
         ReceiveData();
     }
 
     public void ReceiveData()
     {
         if (newSock.Available > 0)
         {
             receivedData = newSock.Receive(ref sender);
             dataString = Encoding.ASCII.GetString(receivedData);
 
             if (Encoding.ASCII.GetString(receivedData) == "jump")
             {
                 Jump(1000);
             }
         }
         else
         {
             print("No data to receive");
         }
     }
 
     public void Jump(int force)
     {
         GetComponent<Rigidbody>().AddForce(Vector3.up * force);
     }
 }

This code as it is now, works for me, I use a basic application outside of unity to send "jump" to my game. Although one thing I noticed for me was that the in editor player would not receive anything through the internet it had to be sent through LAN, and I honestly have no idea why, if anyone knows, cheers.

UdpClient.receive crashes unity

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