UE4 Sockets多线程TCP通信
一、简介
UE4引擎是提供了Sockets模块和Networking模块的，博主在研究此功能时也是参考的Sockets模块和Networking模块的源码，其中引擎为我们提供了一些实例类很有参考价值，比如Sockets模块中的MultichannelTcpReceiver.h和MultichannelTcpSender.h，Networking模块中的UdpSocketReceiver.h和UdpSocketSender.h。博主的例子就是研究参考了以上代码写出来的。
编译与运行环境
UnrealEngine 4.15 ， Visual Studio 2015
实现功能介绍
博主的例子实现的是一个使用Socket多线程TCP通信的客户端。在主线程中发消息，子线程中收消息。当然也能类似的实现两个子线程分别收发消息。Socket相关函数都定义在了GameInstance中，以便我们能在不同场景都能调用。
二、代码实现
服务器代码
此处使用了一个有简单收发功能的服务器，用VS2015新建空项目即可：
//SocketTest.cpp: Defines the entry point for the console application
#include 模块添加
新建项目，在.Build.cs文件中添加Sockets模块和Networking模块：
// Copyright 1998-2017 Epic Games, Inc. All Rights Reserved.
using UnrealBuildTool;
public class SocketThread : ModuleRules
{
public SocketThread(TargetInfo Target)
{
PublicDependencyModuleNames.AddRange(new string[] { "Core", "CoreUObject", "Engine", "InputCore", "HeadMountedDisplay","Sockets", "Networking" });
}
}Socket相关函数定义
STGameInstance.h
//this is the STGameInstance.h
#pragma once
#include "Engine/GameInstance.h"
#include "Networking.h"
#include "ReceiveThread.h"
#include "STGameInstance.generated.h"
UCLASS()
class SOCKETTHREAD_API USTGameInstance : public UGameInstance
{
GENERATED_BODY()
public:
//创建Socket并连接到服务器（主线程）
UFUNCTION(BlueprintCallable, Category = "MySocket")
bool SocketCreate(FString IPStr, int32 port);
//发消息(主线程)
UFUNCTION(BlueprintCallable, Category = "MySocket")
bool SocketSend(FString message);
//收消息(子线程)
UFUNCTION(BlueprintCallable, Category = "MySocket")
bool SocketReceive();
UFUNCTION(BlueprintCallable, Category = "MySocket")
bool ThreadEnd();
FString StringFromBinaryArray(TArray<uint8> BinaryArray);
public:
FSocket *Host;
FIPv4Address ip;
FRunnableThread* m_RecvThread;
};
STGameInstance.cpp
//this is the STGameInstance.cpp
#include "SocketThread.h"
#include "STGameInstance.h"
bool USTGameInstance::SocketCreate(FString IPStr, int32 port)
{
FIPv4Address::Parse(IPStr, ip); //将传入的IPStr转为IPv4地址
//创建一个addr存放ip地址和端口
TSharedPtr<FInternetAddr> addr = ISocketSubsystem::Get(PLATFORM_SOCKETSUBSYSTEM)->CreateInternetAddr();
addr->SetIp(ip.Value);
addr->SetPort(port);
//创建客户端socket
Host = ISocketSubsystem::Get(PLATFORM_SOCKETSUBSYSTEM)->CreateSocket(NAME_Stream, TEXT("default"), false);
//连接成功
if (Host->Connect(*addr))
{
UE_LOG(LogTemp, Warning, TEXT("Connect Succeed!"));
return true;
}
//连接失败
else
{
UE_LOG(LogTemp, Warning, TEXT("Connect Failed!"));
return false;
}
}
bool USTGameInstance::SocketSend(FString message)
{
TCHAR *seriallizedChar = message.GetCharArray().GetData();
int32 size = FCString::Strlen(seriallizedChar) + 1;
int32 sent = 0;
if (Host->Send((uint8*)TCHAR_TO_UTF8(seriallizedChar), size, sent))
{
UE_LOG(LogTemp, Warning, TEXT("___Send Succeed!"));
return true;
}
else
{
UE_LOG(LogTemp, Warning, TEXT("___Send Failed!"));
return false;
}
}
bool USTGameInstance::SocketReceive()
{
m_RecvThread = FRunnableThread::Create(new FReceiveThread(Host), TEXT("RecvThread"));
return true;
}
bool USTGameInstance::ThreadEnd()
{
if (m_RecvThread != nullptr)
{
m_RecvThread->Kill(true);
delete m_RecvThread;
}
return true;
}
FString USTGameInstance::StringFromBinaryArray(TArray<uint8> BinaryArray)
{
return FString(ANSI_TO_TCHAR(reinterpret_cast<const char*>(BinaryArray.GetData())));
}收消息线程
ReceiveThread.h
//this is the ReceiveThread.h
#pragma once
#include "ThreadingBase.h"
#include "Networking.h"
class SOCKETTHREAD_API FReceiveThread : public FRunnable
{
public:
FReceiveThread(FSocket* client): m_Client(client)
{}
~FReceiveThread()
{
stopping = true;
}
virtual bool Init() override
{
stopping = false;
return true;
}
virtual uint32 Run() override
{
if (!m_Client)
{
return 0;
}
TArray ReceiveData;
uint8 element = 0;
//接收数据包
while (!stopping) //线程计数器控制
{
ReceiveData.Init(element, 1024u);
int32 read = 0;
m_Client->Recv(ReceiveData.GetData(), ReceiveData.Num(), read);
const FString ReceivedUE4String = FString(ANSI_TO_TCHAR(reinterpret_cast<const char*>(ReceiveData.GetData())));
FString log = "Server:" + ReceivedUE4String;
UE_LOG(LogTemp, Warning, TEXT("*** %s"), *log);
FPlatformProcess::Sleep(0.01f);
}
return 1;
}
virtual void Stop() override
{
stopping = true; //计数器-1
}
private:
FSocket* m_Client; //客户端套接字
bool stopping; //循环控制
FThreadSafeCounter m_StopTaskCounter; //线程引用计数器
}; 三、运行
在编辑器中，创建我们之前定义的GameInstance的蓝图类，并在Project Setting中设其为默认GameInstance。创建一个GameMode，在他的EventGraph中添加如下蓝图逻辑：
其中Succe是一个bool类型变量，Index是一个Int类型变量，不改默认值。
之后将这个GameMode绑定到当前场景中，编译运行服务器，然后Play，大功告成！博主运行结果如下：
可以看到，收发消息都成功了。