C # Use the WMI Object to obtain the system DPI.

Before using the WMI object, you must add a reference to System. Management, and then you can call the WMI Object.
The WMI object we use is: win32_shorttopmonitor.
Object Reference: http://msdn.microsoft.com/zh-cn/library/Aa394122
Code:
Static void Main (string [] args ){

Using (ManagementClass mc = new ManagementClass ("Win32_DesktopMonitor ")){
Using (ManagementObjectCollection moc = mc. GetInstances ()){

Int PixelsPerXLogicalInch = 0; // dpi for x
Int PixelsPerYLogicalInch = 0; // dpi for y

Foreach (ManagementObject each in moc ){
PixelsPerXLogicalInch = int. Parse (each. Properties ["PixelsPerXLogicalInch"]. Value. ToString ()));
PixelsPerYLogicalInch = int. Parse (each. Properties ["PixelsPerYLogicalInch"]. Value. ToString ()));
}

Console. WriteLine ("PixelsPerXLogicalInch:" + PixelsPerXLogicalInch. ToString ());
Console. WriteLine ("PixelsPerYLogicalInch:" + PixelsPerYLogicalInch. ToString ());
Console. Read ();
}

}
}

The above code passes the test in WIN7 environment.

 

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