【小松教你手游開發】【unity系統模塊開發】unity網絡層讀寫

在unity做強聯網游戲的時候一般會選擇用tcp來做通信（據說有一種udp的傳輸具有更高的效率），而接收信息的方法上一般會選擇新建一個線程循環讀取。

今天在我們項目上看到另外的一種方法。這里記錄一下。

首先建立tcp連接

#using System.Net.Sockets;  

TcpClient tcpClient = new TcpClient();  
tcpClient .BeginConnect(address,port,new AsyncCallback(this.OnConnect),result);  

可以看到這里用的是異步通信回調函數AsyncCallback

private void OnConnect(IAsyncResult ar)  
{  
    ConnectResult result = ar.AsyncState as ConnectRsult;  
    try  
    {  
        result.client.EndConnect(ar);  
        int size = HeaderLength;//定好的表頭大小  
        byte[] readBuf = new byte[size];  
        result.client.GetStream().BeginRead(readBuf,0,size,new AsyncCallback(this.OnRead),new RecvIremObject(result.client,readBuf,size));  
    }  
    catch(System.Net.Sockets.SocketException e)  
    {  
    }  
}  

上面是連接成功后的函數，連接成功后就可以斷開連接并開始接受表頭；同樣是在異步通信回調函數內使用

private void OnRead(IAsyncResult ar)  
{  
    RecvItemObject item = (RecvItemObject)ar.AsyncState;  
    try  
    {  
        Stream stram = item.client.GetStram();  
        int readsize = stream.EndRead(ar);  
        item.current =+= readsize;  
        TotalReadSize += (uint)readsize;  
        if(item.current < item.total)  
        {  
            item.client.GetStram().BeginRead(ite.bufs,item.current,item.total - item.current,new AsyncCallback(OnRead)，item);  
        }  
        else  
        {  
            if(item.state == RecvItemObject.EndReadState.ReadHearder)  
            {  
                //上面就是讀取信息邏輯,數據在item.bufs里，自己按需求解析  
                //下面計算是否讀完包頭，下次應該讀包還是包頭  
                if(true)  
                {  
                    item.client.GetStram().BeginRead(item.bufs,0,bufsSize,new AsyncCallback(this.OnRead),item);  
                }  
                else  
                {  
                    item.client.GetStram().BeginRead(item.bufs,0,dataLength,new AsyncCallback(this.OnRead),item);  
                }  

            }  
            else(item.state == RecvItemObject.EndReadState.ReadData)  
            {  
                //上面就是讀取信息邏輯  
                //下次應該讀包頭  
                item.client.GetStram().BeginRead(item.bufs,0,bufsSize,new AsyncCallback(this.OnRead),item);  
            }  
        }  

    }  
}  

可以看到，這種方式也就是一直通過調用異步加載函數AsyncCallback
來實現一直讀取信息
而上面用的的BeginRead()函數的最后一個參數item是自己定義的一個數據類，函數的這個參數是用來下次異步回調的時候把上次的item傳給下個回調

private class RecvItemObject  
{  
    public enum EReadState  
    {  
        ReadData,  
        ReadHeader,  
    }  
    public byte[] bufs;  
    public int total;  
    public int current;  
    public EReadState state;  
    public TcpClient client;  
    public NetworkStram networkStream;  

    public RecvItemObject(TcpClient client, byte[] bufs,int total)  
    {  
        this.client = client;  
        this.bufs = bufs;  
        this.total = total;  
        current =0;  
        state = EReadState.ReadHeader;  

    }  
}  

而寫數據呢，是在游戲的Update里發送，加一條發送信息就在隊列里加一個，在Update里檢測如果隊列里有需要發送的數據就寫數據

public void UpdateSend()  
{  
    //填寫數據  
     try  
     {  
        NetworkStream stream = tcpCLient.getStream();  
        if(stream.CanWrite)  
        {  
            //pMsg數據Byte[]  
            stream.BeginWtrite(pMsg,0,pMsg.Length,new AsycCallback(this.OnWrite),tcpCLient);  
        }  

     }  
    catch(SocketException e)  
    {  
    }  
} 

在發送完了以后會跑到上面的異步回掉OnWrite里。在里面把流關閉寫入

private void OnWrite(IAsyncResult ar)  
{  
    TcpClient client = (TcpClient)ar.AsyncState;  
    try  
    {  
        client.GetStream().EndWrite(ar);  
    }  
    catch(SocketException e)  
    {  
    }  
}