刚接触windows 不同程序 窗口消息传递,不理解IntPtr SendMessage(int hWnd, int msg, IntPtr wParam, IntPtr lParam)这函数怎么用?消息内容怎么传递过去,还遇到需要message结构体?IntPtr怎么用呢?
但实际只是用来传个数据,不需要这么复杂,就简单写了下面程序。
1.发送端
public partial class Form1 : Form{private const int WM_USER = 0x0400; //自定义消息号一般开始于0x0400,[DllImport("User32.dll", EntryPoint = "SendMessage")]private static extern IntPtr SendMessage(int hWnd, int msg, IntPtr wParam, IntPtr lParam); //发送消息函数。//找出窗口句柄handler,用起来方便。有看到过返回值时IntPtr[DllImport("User32.dll", EntryPoint = "FindWindow")]private static extern int FindWindow(string lpClassName, string lpWindowName); public Form1(){InitializeComponent();this.Text = "消费者";label1.Text = "向X300A";}private void button1_Click(object sender, EventArgs e){int WINDOW_HANDLER; //int msgNum;if(int.TryParse(textBox1.Text,out msgNum)==false) //获取用户信息内容,这里只接受数字。{return;}WINDOW_HANDLER = FindWindow(null, "X300A");//通过窗口标题,获得句柄SendMessage(WINDOW_HANDLER, WM_USER, new IntPtr(msgNum), IntPtr.Zero);//前面两个参数,基本固定格式。//后面两个参数,把需要传递的参数转为IntPtr,就好了。//第四个参数因为没什么传的,这里就设为空}}
2.接收端
public partial class Form1 : Form{private const int WM_USER = 0x0400; //自定义消息号一般开始于0x0400,发送端也是设置成这个public Form1(){InitializeComponent();this.Text = "X300A";label1.Text = "接收消费者信息";}protected override void WndProc(ref Message m) //重新函数,处理接收的信息{switch (m.Msg){case WM_USER:string message = m.WParam.ToString(); //转换成string类型,这样就能接收到发送端信息。textBox1.AppendText("接受到信息:"+message+"\n");Popup p1 = new Popup(); //自定义的一个窗口if(p1.ShowDialog()==DialogResult.OK) {p1.Dispose();textBox1.AppendText("启动完毕\n");}break;default: break;}base.WndProc(ref m);}}
3.演示图
参考链接:
http://blog.sina.com.cn/s/blog_45eaa01a01013zbs.html