问题描述
我试图让显示所有显示器和监视器名称的功能。
，而第2次我叫enumDisplayDevices，如果第一个参数是lpDisplayDevice.DeviceName有一个错误。我知道这是第一个参数监守如果它被设置为IntPtr.Zero代替，没有错误。
我无法找到如何做到这一点在C＃中的另一个例子。
公共静态无效show_display_devices（）
{
DISPLAY_DEVICE lpDisplayDevice =新DISPLAY_DEVICE（0）; // OUT
INT DEVNUM = 0;
，而（真）
{
BOOL成功= EnumDisplayDevices（IntPtr.Zero，DEVNUM，参考lpDisplayDevice，0）;
如果
断点（成功！）;
Console.WriteLine（\\\
devNum =+ DEVNUM）;
Console.WriteLine（CB =+ lpDisplayDevice.cb）;
Console.WriteLine（的DeviceID =+ lpDisplayDevice.DeviceID）;
Console.WriteLine（DeviceKey =+ lpDisplayDevice.DeviceKey）;
Console.WriteLine（设备名称=+ lpDisplayDevice.DeviceName.Trim（））;
Console.WriteLine（DeviceString =+ lpDisplayDevice.DeviceString.Trim（））;
//显示监视器名称：
DISPLAY_DEVICE monitor_name =新DISPLAY_DEVICE（0）; // OUT
个;>>>>>>>>>>下一行有错误：其中;<<<<<<<<<<<<<<
EnumDisplayDevices（lpDisplayDevice.DeviceName，0，参考monitor_name，0）; <<<<<<<<<<<<<<<<< lpDisplayDevice.DeviceName会导致错误<<<<<<
^^^^^^^^^^^^^^^^^^^^^^^^^^ - 导致错误<<<<<<
Console.WriteLine（监视器名称=+ lpDisplayDevice.DeviceString.Trim（））;
++ DEVNUM;
}
}
的问题是，在申报的私人静态外部布尔EnumDisplayDevices（）。我改变了lpDevice从IntPtr的字符串，它为我的作品
下面的源代码在输出窗口中的以下内容：
DEVNUM = 0
CB = 424
的DeviceID = PCI\VEN_10DE&放大器; DEV_0402&安培; SUBSYS_0440196E&安培; REV_A1
DeviceKey = \Registry\Machine\System\CurrentControlSet \Control\Video {B757E378-AF2E-4826-BA9E-927C5B81B139} \0000
设备名称= \.\DISPLAY1
DeviceString =的NVIDIA GeForce 8600 GT
线程'RunPowerStatusMonitor主题（0x2108）已与代码0（为0x0）退出。
监视器名称=通用即插即用监视器
DEVNUM = 1
CB = 424
的DeviceID = PCI\VEN_10DE&放大器; DEV_0402&安培; SUBSYS_0440196E&安培; REV_A1
DeviceKey = {\Registry\Machine\System\CurrentControlSet\Control\Video B757E378-AF2E-4826-BA9E-927C5B81B139} \0001
设备名称= \.\ DISPLAY2
DeviceString = NVIDIA的GeForce 8600 GT
监视器名称=通用即插即用监视器
公共静态无效show_display_devices（ ）
{
DISPLAY_DEVICE lpDisplayDevice =新DISPLAY_DEVICE（0）; // OUT
DISPLAY_DEVICE monitor_name =新DISPLAY_DEVICE（0）; // OUT
INT DEVNUM = 0;
，而（EnumDisplayDevices（NULL，DEVNUM，参考lpDisplayDevice，0））
{
Console.WriteLine（\\\
devNum =+ DEVNUM）;
Console.WriteLine（CB =+ lpDisplayDevice.cb）;
Console.WriteLine（的DeviceID =+ lpDisplayDevice.DeviceID）;
Console.WriteLine（DeviceKey =+ lpDisplayDevice.DeviceKey）;
Console.WriteLine（设备名称=+ lpDisplayDevice.DeviceName.Trim（））;
Console.WriteLine（DeviceString =+ lpDisplayDevice.DeviceString.Trim（））;
//显示监视器名称：
EnumDisplayDevices（lpDisplayDevice.DeviceName，0，参考monitor_name，0）;
Console.WriteLine（监视器名称=+ monitor_name.DeviceString.Trim（））;
++ DEVNUM;
}
}
函数[DllImport（User32.dll中）]
私人静态外部布尔EnumDisplayDevices（
串lpDevice，INT iDevNum，
REF DISPLAY_DEVICE lpDisplayDevice，诠释的dwFlags）;
[StructLayout（LayoutKind.Sequential）]
公共结构DISPLAY_DEVICE
{
公众诠释CB;
[的MarshalAs（UnmanagedType.ByValTStr，SizeConst = 32）]
公共字符串设备名称;
[的MarshalAs（UnmanagedType.ByValTStr，SizeConst = 128）]
公共字符串DeviceString;
公众诠释StateFlags;
[的MarshalAs（UnmanagedType.ByValTStr，SizeConst = 128）]
公共字符串的DeviceID;
[的MarshalAs（UnmanagedType.ByValTStr，SizeConst = 128）]
公共字符串DeviceKey;
公共DISPLAY_DEVICE（INT标志）
{
CB = 0;
StateFlags =标志;
设备名称=新的字符串（（CHAR）32，32）;
DeviceString =新的字符串（（char）的32，128）;
的DeviceID =新的字符串（（char）的32，128）;
DeviceKey =新的字符串（（char）的32，128）;
CB = Marshal.SizeOf（本）;
}
}
I'm trying to make a function that displays all display and monitor names.But the 2nd time I call enumDisplayDevices, there's an error if the first argument is lpDisplayDevice.DeviceName. I know it's the first argument becuase if it's set to "IntPtr.Zero" instead, there is no error.
I cannot find another example of how to do this in C#.
public static void show_display_devices()
{
DISPLAY_DEVICE lpDisplayDevice = new DISPLAY_DEVICE(0); // OUT
int devNum = 0;
while(true)
{
bool success = EnumDisplayDevices( IntPtr.Zero, devNum, ref lpDisplayDevice, 0);
if( !success )
break;
Console.WriteLine("\ndevNum =" + devNum);
Console.WriteLine("cb =" + lpDisplayDevice.cb);
Console.WriteLine("DeviceID =" + lpDisplayDevice.DeviceID);
Console.WriteLine("DeviceKey =" + lpDisplayDevice.DeviceKey);
Console.WriteLine("DeviceName =" + lpDisplayDevice.DeviceName.Trim());
Console.WriteLine("DeviceString =" + lpDisplayDevice.DeviceString.Trim());
// Show monitor name:
DISPLAY_DEVICE monitor_name = new DISPLAY_DEVICE(0); // OUT
>>>>>>>>>>> NEXT LINE HAS ERROR: <<<<<<<<<<<<<<<
EnumDisplayDevices(lpDisplayDevice.DeviceName, 0, ref monitor_name, 0); <<<<<<<<<<<<<<<<< "lpDisplayDevice.DeviceName" causes error <<<<<<
^^^^^^^^^^^^^^^^^^^^^^^^^^ - CAUSES ERROR <<<<<<
Console.WriteLine("Monitor name =" + lpDisplayDevice.DeviceString.Trim());
++devNum;
}
}
The problem was in the declaration "private static extern bool EnumDisplayDevices()". I changed lpDevice from IntPtr to string, and it works for me.
The source code below produces the following in the Output window:
devNum =0cb =424DeviceID =PCI\VEN_10DE&DEV_0402&SUBSYS_0440196E&REV_A1DeviceKey =\Registry\Machine\System\CurrentControlSet\Control\Video{B757E378-AF2E-4826-BA9E-927C5B81B139}\0000DeviceName =\.\DISPLAY1DeviceString =NVIDIA GeForce 8600 GTThe thread 'RunPowerStatusMonitor Thread' (0x2108) has exited with code 0 (0x0).Monitor name =Generic PnP Monitor
devNum =1cb =424DeviceID =PCI\VEN_10DE&DEV_0402&SUBSYS_0440196E&REV_A1DeviceKey =\Registry\Machine\System\CurrentControlSet\Control\Video{B757E378-AF2E-4826-BA9E-927C5B81B139}\0001DeviceName =\.\DISPLAY2DeviceString =NVIDIA GeForce 8600 GTMonitor name =Generic PnP Monitor
public static void show_display_devices()
{
DISPLAY_DEVICE lpDisplayDevice = new DISPLAY_DEVICE(0); // OUT
DISPLAY_DEVICE monitor_name = new DISPLAY_DEVICE(0); // OUT
int devNum = 0;
while (EnumDisplayDevices(null, devNum, ref lpDisplayDevice, 0))
{
Console.WriteLine("\ndevNum =" + devNum);
Console.WriteLine("cb =" + lpDisplayDevice.cb);
Console.WriteLine("DeviceID =" + lpDisplayDevice.DeviceID);
Console.WriteLine("DeviceKey =" + lpDisplayDevice.DeviceKey);
Console.WriteLine("DeviceName =" + lpDisplayDevice.DeviceName.Trim());
Console.WriteLine("DeviceString =" + lpDisplayDevice.DeviceString.Trim());
// Show monitor name:
EnumDisplayDevices( lpDisplayDevice.DeviceName, 0, ref monitor_name, 0);
Console.WriteLine("Monitor name =" + monitor_name.DeviceString.Trim());
++devNum;
}
}
[DllImport("User32.dll")]
private static extern bool EnumDisplayDevices(
string lpDevice, int iDevNum,
ref DISPLAY_DEVICE lpDisplayDevice, int dwFlags);
[StructLayout(LayoutKind.Sequential)]
public struct DISPLAY_DEVICE
{
public int cb;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)]
public string DeviceName;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
public string DeviceString;
public int StateFlags;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
public string DeviceID;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
public string DeviceKey;
public DISPLAY_DEVICE(int flags)
{
cb = 0;
StateFlags = flags;
DeviceName = new string((char)32, 32);
DeviceString = new string((char)32, 128);
DeviceID = new string((char)32, 128);
DeviceKey = new string((char)32, 128);
cb = Marshal.SizeOf(this);
}
}
这篇关于C＃如何获得Windows监视器名称的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！