第二步、在托管环境下对Win 32 函数进行声明：
// Win32 函数在托管环境下的声明
public class NativeMethods
{
// 平台调用的申明
[DllImport("user32.dll")]
public static extern int EnumDisplaySettings(
string deviceName, int modeNum, ref DEVMODE devMode);
[DllImport("user32.dll")]
public static extern int ChangeDisplaySettings(
ref DEVMODE devMode, int flags);
// 控制改变屏幕分辨率的常量
public const int ENUM_CURRENT_SETTINGS = -1;
public const int CDS_UPDATEREGISTRY = 0x01;
public const int CDS_TEST = 0x02;
public const int DISP_CHANGE_SUCCESSFUL = 0;
public const int DISP_CHANGE_RESTART = 1;
public const int DISP_CHANGE_FAILED = -1;
// 控制改变方向的常量定义
public const int DMDO_DEFAULT = 0;
public const int DMDO_90 = 1;
public const int DMDO_180 = 2;
public const int DMDO_270 = 3;
}
第三步、调用EnumDisplaySettings和ChangeDisplaySettings这两个函数来实现动态改变屏幕分辨率，具体代码如下：
// 改变分辨率
public ChangeResolution(int width, int height)
{
// 初始化 DEVMODE结构
DEVMODE devmode = new DEVMODE();
devmode.dmDeviceName = new String(new char[32]);
devmode.dmFormName = new String(new char[32]);
devmode.dmSize = (short)Marshal.SizeOf(devmode);
if (0 != NativeMethods.EnumDisplaySettings(null, NativeMethods.ENUM_CURRENT_SETTINGS, ref devmode))
{
devmode.dmPelsWidth = width;
devmode.dmPelsHeight = height;
// 改变屏幕分辨率
int iRet = NativeMethods.ChangeDisplaySettings(ref devmode, NativeMethods.CDS_TEST);
if (iRet == NativeMethods.DISP_CHANGE_FAILED)
{
MessageBox.Show("不能执行你的请求", "信息", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
else
{
iRet = NativeMethods.ChangeDisplaySettings(ref devmode, NativeMethods.CDS_UPDATEREGISTRY);
switch (iRet)
{
// 成功改变
case NativeMethods.DISP_CHANGE_SUCCESSFUL:
{
break;
}
case NativeMethods.DISP_CHANGE_RESTART:
{
MessageBox.Show("你需要重新启动电脑设置才能生效", "信息", MessageBoxButtons.OK, MessageBoxIcon.Information);
break;
}
default:
{
MessageBox.Show("改变屏幕分辨率失败", "信息", MessageBoxButtons.OK, MessageBoxIcon.Information);
break;
}
}
}
}
}
为了大家更加形象地看到程序的运行结果，下面是一个演示效果：
