至少有一次或两次，当我运行我的程序时它被冻结了，我无法单击任何按钮，甚至无法关闭它，因为表单被冻结了。
在其他时候，有时当我退出（表单关闭）时，程序就会冻结。我尝试在每个方法中添加 try 和 catch，但它永远不会停在那里。
这是我的 Form1 和构造函数的顶部：
public partial class Form1 : Form
{
private bool quitwithtimer;
private int y;
private int x;
private IntPtr ID;
private int counter;
private int minutes;
private int seconds;
private DateTime dt;
[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
internal static extern bool SetLocalTime(ref SYSTEMTIME lpSystemTime);
[StructLayout(LayoutKind.Sequential)]
internal struct SYSTEMTIME
{
public ushort wYear;
public ushort wMonth;
public ushort wDayOfWeek; // ignored for the SetLocalTime function
public ushort wDay;
public ushort wHour;
public ushort wMinute;
public ushort wSecond;
public ushort wMilliseconds;
}
private int day;
private int month;
private int year;
private int hour;
private int minute;
public Form1()
{
InitializeComponent();
label1.ForeColor = Color.Red;
label1.Text = "Test";
label1.Font = new Font(label1.Font.FontFamily, label1.Font.Size + 8f, label1.Font.Style);
TimerCount.Text = "00:00";
quitwithtimer = false;
x = Screen.PrimaryScreen.Bounds.Bottom - this.Width * 2;
y = Screen.PrimaryScreen.Bounds.Bottom - this.Height * 2;
counter = x;
ID = this.Handle; //get handle of form
minutes = 5;
seconds = 0;
}
[DllImport("user32.dll", SetLastError = true)]
internal static extern bool MoveWindow(IntPtr hWnd, int X, int Y, int nWidth, int nHeight, bool bRepaint);
有时这个 DllImport 可能会导致问题之一？
我有这种方法来获取当前时间和日期，但是当程序冻结时它永远不会被捕获。
public static DateTime GetNetworkTime()
{
DateTime networkDateTime = DateTime.Now;
try
{
IPAddress[] addresses = null;
//default Windows time server
const string ntpServer = "time.windows.com";
const string ntpServer1 = "time.nist.gov";
const string ntpServer2 = "time-nw.nist.gov";
const string ntpServer3 = "time-a.nist.gov";
const string ntpServer4 = "time-b.nist.gov";
List<string> ntpServersList = new List<string>();
ntpServersList.Add(ntpServer);
ntpServersList.Add(ntpServer1);
ntpServersList.Add(ntpServer2);
ntpServersList.Add(ntpServer3);
ntpServersList.Add(ntpServer4);
// NTP message size - 16 bytes of the digest (RFC 2030)
var ntpData = new byte[48];
//Setting the Leap Indicator, Version Number and Mode values
ntpData[0] = 0x1B; //LI = 0 (no warning), VN = 3 (IPv4 only), Mode = 3 (Client Mode)
for (int i = 0; i < ntpServersList.Count; i++)
{
addresses = Dns.GetHostEntry(ntpServersList[i]).AddressList;
if (addresses.Length > 0)
{
break;
}
}
//The UDP port number assigned to NTP is 123
var ipEndPoint = new IPEndPoint(addresses[0], 123);
//NTP uses UDP
var socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
socket.Connect(ipEndPoint);
socket.Send(ntpData);
socket.Receive(ntpData);
socket.Close();
//Offset to get to the "Transmit Timestamp" field (time at which the reply
//departed the server for the client, in 64-bit timestamp format."
const byte serverReplyTime = 40;
//Get the seconds part
ulong intPart = BitConverter.ToUInt32(ntpData, serverReplyTime);
//Get the seconds fraction
ulong fractPart = BitConverter.ToUInt32(ntpData, serverReplyTime + 4);
//Convert From big-endian to little-endian
intPart = SwapEndianness(intPart);
fractPart = SwapEndianness(fractPart);
var milliseconds = (intPart * 1000) + ((fractPart * 1000) / 0x100000000L);
//**UTC** time
networkDateTime = (new DateTime(1900, 1, 1, 0, 0, 0, DateTimeKind.Utc)).AddMilliseconds((long)milliseconds);
}
catch(Exception err)
{
MessageBox.Show("error" + err.ToString());
}
return networkDateTime.ToLocalTime();
}
// stackoverflow.com/a/3294698/162671
static uint SwapEndianness(ulong x)
{
return (uint)(((x & 0x000000ff) << 24) +
((x & 0x0000ff00) << 8) +
((x & 0x00ff0000) >> 8) +
((x & 0xff000000) >> 24));
}
在运行程序时以及在大多数情况下从程序中退出时，有时会导致程序冻结一次/两次。
private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
try
{
if (MessageBox.Show("Are you sure you want to close the form?", "Close Form",
MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.No)
{
e.Cancel = true;
}
else
{
timer1.Enabled = false;
timer2.Enabled = false;
ChangeTimeOriginal();
}
}
catch (Exception err)
{
MessageBox.Show("Error" + err.ToString());
}
}
更改时间原始（）
private void ChangeTimeOriginal()
{
try
{
dt = GetNetworkTime();
day = dt.Day;
month = dt.Month;
year = dt.Year;
hour = dt.Hour;
minute = dt.Minute;
SYSTEMTIME time = new SYSTEMTIME();
time.wDay = (ushort)day;
time.wMonth = (ushort)month;
time.wYear = (ushort)year;
time.wHour = (ushort)hour;
time.wMinute = (ushort)minute;
if (!SetLocalTime(ref time))
{
// The native function call failed, so throw an exception
throw new Win32Exception(Marshal.GetLastWin32Error());
}
}
catch (Exception err)
{
MessageBox.Show("Error" + err.ToString());
}
}
我怎样才能找到问题？
编辑**
这就是我在程序冻结和暂停时在右下角的调用堆栈窗口中看到的所有内容。
它走到了这条线上：socket.Receive(ntpData); 在 GetNetworkTime() 方法中。
这就是我现在在调用堆栈窗口中看到的内容：
[External Code]
> TestDateTime.exe!TestDateTime.Form1.GetNetworkTime() Line 122 + 0xd bytes C#
TestDateTime.exe!TestDateTime.Form1.ChangeTimeOriginal() Line 272 + 0xe bytes C#
TestDateTime.exe!TestDateTime.Form1.Form1_FormClosing(object sender, System.Windows.Forms.FormClosingEventArgs e) Line 225 + 0x8 bytes C#
[External Code]
TestDateTime.exe!TestDateTime.Program.Main() Line 19 + 0x1d bytes C#
[External Code]