windows mobile来电

Question

namespace Comer
{
    public partial class Form1 : Form
    {
        public Form1()
        {   
            InitializeComponent();
        }
        public void ListenCall()
        {   
            SystemState callState = new SystemState(SystemProperty.PhoneCallTalking);
            SystemState callCount = new SystemState(SystemProperty.PhoneActiveCallCount);
            callState.Changed += new ChangeEventHandler(callState_Changed);
            callCount.Changed += new ChangeEventHandler(callCount_Changed);
        }        public void callCount_Changed(object sender, ChangeEventArgs args)
        {
            if (args.NewValue != null && (int)args.NewValue != 0)
                MessageBox.Show("Call Incoming");
        }        public void callState_Changed(object sender, ChangeEventArgs args)
        {
            if (args.NewValue != null)
            {
                String state = ((int)args.NewValue) == 1 ? "talking" : "hang up";
                MessageBox.Show(state);
            }
        }
    }
}
帮我看一下那有错误啊（能生成）怎么测试时不反应啊。。

Answer 1

此ListenCall()没有触发，  你不妨这样写 public Form1()
  {   
  InitializeComponent();
   ListenCall()
  }