当我运行我的程序时，至少一次或两次冻结，我无法点击任何按钮，甚至关闭它，因为表格冻结。
在其他时候，有时当我退出（表格结束）时，程序就会冻结。 我试图为每个方法添加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会出现问题吗？
我有这种方法来获取当前的时间和日期，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，程序有时会冻结一次/两次，在大多数情况下从程序中退出时，可能会使程序冻结。
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());
}
}
ChangeTimeOriginal（）
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**
这就是我所看到的以及当程序冻结时以及当我执行PAUSE时右下角的调用堆栈窗口。
它去了一行：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]
答案 0 :(得分：4)
看起来您的应用程序冻结的原因是因为您正在调用GetNetworkTime()，这反过来又会阻止IO阻塞调用时间服务器。您应该考虑重新处理此代码以在工作线程上进行这些IO阻塞调用。在工作线程上获取结果后，您可以通过Invoke()或BeginInvoke()构造将此数据传递回UI线程。看一下应该有用的this tutorial。