C# API 获取系统DPI缩放倍数跟分辨率大小

using System;




using System.Drawing;




using System.Runtime.InteropServices;



 




namespace XYDES




{



    public class PrimaryScreen




    {



        #region Win32 API




                [DllImport("user32.dll")]



                 static extern IntPtr GetDC(IntPtr ptr);



                [DllImport("gdi32.dll")]



                 static extern int GetDeviceCaps(




                IntPtr hdc, // handle to DC



                int nIndex // index of capability



                );



                [DllImport("user32.dll", EntryPoint = "ReleaseDC")]



                 static extern IntPtr ReleaseDC(IntPtr hWnd, IntPtr hDc);



        #endregion




        #region DeviceCaps常量




                const int HORZRES = 8;



                const int VERTRES = 10;



                const int LOGPIXELSX = 88;



                const int LOGPIXELSY = 90;



                const int DESKTOPVERTRES = 117;



                const int DESKTOPHORZRES = 118;



        #endregion




 



        #region 属性




        /// 





        /// 获取屏幕分辨率当前物理大小




        /// 




           public static Size WorkingArea



            {



                get {



                    IntPtr hdc = GetDC(IntPtr.Zero);



                    Size size = new Size();



                    size.Width = GetDeviceCaps(hdc, HORZRES);



                    size.Height = GetDeviceCaps(hdc, VERTRES);



                    ReleaseDC(IntPtr.Zero, hdc);



                    return size;    



                }



            }



        /// 





           /// 当前系统DPI_X 大小 一般为96




        /// 




            public static int DpiX



            {



                get




                {



                    IntPtr hdc = GetDC(IntPtr.Zero);



                    int DpiX = GetDeviceCaps(hdc, LOGPIXELSX );



                    ReleaseDC(IntPtr.Zero, hdc);



                    return DpiX;



                }



            }



        /// 





        /// 当前系统DPI_Y 大小 一般为96




        /// 




            public static int DpiY



            {



                get




                {



                    IntPtr hdc = GetDC(IntPtr.Zero);



                    int DpiX = GetDeviceCaps(hdc,LOGPIXELSY);



                    ReleaseDC(IntPtr.Zero, hdc);



                    return DpiX;



                }



            }



        /// 





            /// 获取真实设置的桌面分辨率大小




        /// 




            public static Size DESKTOP



            {



                get




                {



                    IntPtr hdc = GetDC(IntPtr.Zero);



                    Size size = new Size();



                    size.Width = GetDeviceCaps(hdc,DESKTOPHORZRES );



                    size.Height = GetDeviceCaps(hdc, DESKTOPVERTRES);



                    ReleaseDC(IntPtr.Zero, hdc);



                    return size;    



                }



            }



 



            /// 





            /// 获取宽度缩放百分比




            /// 




            public static float ScaleX



            {



                get




                {



                    IntPtr hdc = GetDC(IntPtr.Zero);



                    int t = GetDeviceCaps(hdc, DESKTOPHORZRES);



                    int d = GetDeviceCaps(hdc, HORZRES);



                    float ScaleX = (float)GetDeviceCaps(hdc, DESKTOPHORZRES) / (float)GetDeviceCaps(hdc, HORZRES); 



                    ReleaseDC(IntPtr.Zero, hdc);



                    return ScaleX;



                }



            }



            /// 





            /// 获取高度缩放百分比




            /// 




            public static float ScaleY



            {



                get




                {



                    IntPtr hdc = GetDC(IntPtr.Zero);



                    float ScaleY = (float)(float)GetDeviceCaps(hdc, DESKTOPVERTRES) / (float)GetDeviceCaps(hdc, VERTRES);



                    ReleaseDC(IntPtr.Zero, hdc);



                    return ScaleY;



                }



            }



       #endregion




    }



}