1using System;
2using System.Collections.Generic;
3using System.ComponentModel;
4using System.Data;
5using System.Drawing;
6using System.Text;
7using System.Windows.Forms;
8
9using NBear.MQ.ServiceMQ;
10using NBear.MQ;
11using NBear.Common;
12using NBear.Common.Remoting;
13
14namespace TestClientApp
15{
16 public partial class Form1 : Form
17 {
18 public Form1()
19 {
20 InitializeComponent();
21 }
22
23 private void Form1_Load(object sender, EventArgs e)
24 {
25 comboOP.SelectedIndex = 0;
26
27 rh = new RemotingClientHelper(RemotingChannelType.TCP, "127.0.0.1", 8000, 0, new LogHandler(Console.WriteLine));
28 mq = rh.GetClientInstance<IServiceMQ>("MMQ");
29 mq.OnLog = new LogHandler(Console.WriteLine);
30 container = new SimpleServiceContainer(mq);
31 }
32
33 private void txtX_TextChanged(object sender, EventArgs e)
34 {
35 txtResult.Text = string.Empty;
36 }
37
38 private void comboOP_SelectedIndexChanged(object sender, EventArgs e)
39 {
40 txtResult.Text = string.Empty;
41 }
42
43 private void txtY_TextChanged(object sender, EventArgs e)
44 {
45 txtResult.Text = string.Empty;
46 }
47
48 RemotingClientHelper rh = null;
49 IServiceMQ mq = null;
50 IServiceContainer container = null;
51
52 private void btnCompute_Click(object sender, EventArgs e)
53 {
54 try
55 {
56 int.Parse(txtX.Text);
57 if (comboOP.SelectedIndex == 3)
58 {
59 if (int.Parse(txtY.Text) != 0)
60 {
61 }
62 }
63 else
64 {
65 int.Parse(txtY.Text);
66 }
67 }
68 catch
69 {
70 MessageBox.Show("x, y must be number, and y must not be 0 when OP is '/'!");
71 return;
72 }
73
74 RequestMessage msg = new RequestMessage();
75 msg.Expiration = DateTime.Now.AddDays(1);
76 msg.MessageId = Guid.NewGuid();
77 msg.Parameters = new Parameter[] { new Parameter("op", comboOP.Text), new Parameter("x", int.Parse(txtX.Text)), new Parameter("y", int.Parse(txtY.Text)) };
78 msg.ServiceName = "demo.math";
79 msg.Timestamp = DateTime.Now;
80 msg.TransactionId = Guid.NewGuid();
81
82 ResponseMessage retMsg = container.CallService(msg.ServiceName, msg);
83
84 if (retMsg != null)
85 {
86 txtResult.Text = retMsg.Parameters[0].Value.ToString();
87 }
88 else
89 {
90 MessageBox.Show("Call service failed!");
91 }
92 }
93
94 private void btnHelloWorld_Click(object sender, EventArgs e)
95 {
96 RequestMessage msg = new RequestMessage();
97 msg.Expiration = DateTime.Now.AddDays(1);
98 msg.MessageId = Guid.NewGuid();
99 msg.ServiceName = "demo.helloworld";
100 msg.Timestamp = DateTime.Now;
101 msg.TransactionId = Guid.NewGuid();
102
103 msg.Text = "who r u?";
104
105 ResponseMessage retMsg = container.CallService(msg.ServiceName, msg);
106
107 MessageBox.Show(retMsg.Text);
108 }
109 }
110} 

    Line 23-31 在Form Load是初始化container，这和service host是完全一样的。
    调用service只需通过container.CallService方法，如Line 82 和 105。

    问题

    1、您可能会问，client的代码除了调用service和service host的代码几乎相同，那么是否可以在client中既使用service又提供service呢 ？当然可以，你也完全可以在client这里register service，当client调用一个service时，container会首先检查是否存在本地service，存在则调用本地，不存在则向server请求远程service。

    2、本示例是在一台服务器上演示这个分布式构架，您也可以修改地址，并分别把server， service host和client部署到互相连接的多台server上。

    运行

    请按如下顺序执行bin中的代码：TestRemotingServer.exe， TestServiceHost.exe，TestClientApp.exe，ServiceHost和Client可以是多个，server将自动随机分配调用service的请求到各个service host进行处理。在运行过程中，请尝试多次点击client的按钮，并观察，server和service host的日志，看是不是负载均衡。您也可以尝试在运行过程中关闭某些service host或client，或者再新增一些，注意server会自动维护service host和client的绑定和回调。