定时器事件在设备锁定时不起作用

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问题描述

我开发了Windows Mobile 6.5应用程序。

我使用了一个计时器事件，此事件将GPS数据插入到一个表中。

它在正常时间正常工作，但是当设备进入锁定/睡眠模式时，当我恢复到应用程序它正在抛出异常并退出应用程序并且它要求时，它无法正常工作重启应用程序。

I have developed Windows Mobile 6.5 application .
i used one timer event ,this event captured the GPS data insert in to one table.
it is working properly in normal time but when device gets locked/sleep mode , It is not working when i ever i get resumed to the application it is throwing exception and exit the application and it is asking to restart the application.

推荐答案

public const int PPN_UNATTENDEDMODE = 0x0003;
    public const int POWER_NAME = 0x00000001;
    public const int POWER_FORCE = 0x00001000;

    [DllImport("coredll.dll")]
    public static extern bool PowerPolicyNotify(int dwMessage, bool dwData);

    [DllImport("coredll.dll", SetLastError = true)]
    public static extern IntPtr SetPowerRequirement(string pvDevice, CedevicePowerStateState deviceState, uint deviceFlags, string pvSystemState, ulong stateFlags);

    [DllImport("coredll.dll", SetLastError = true)]
    public static extern int ReleasePowerRequirement(IntPtr hPowerReq);

    public enum CedevicePowerStateState : int
    {
        PwrDeviceUnspecified = -1,
        D0 = 0,
        D1,
        D2,
        D3,
        D4,
    }

    //Keep the GPS and device alive:
    PowerPolicyNotify(PPN_UNATTENDEDMODE, true)
    IntPtr gpsPowerHandle = SetPowerRequirement("gpd0:", CedevicePowerStateState.D0, POWER_NAME | POWER_FORCE, null, 0);

    //Call before exiting your app:
    ReleasePowerRequirement(gpsPowerHandle);
    PowerPolicyNotify(PPN_UNATTENDEDMODE, false);