c# - DllImport 放在哪里？

Question

static class Class    
{
    public static void methodRequiringStuffFromKernel32()
    {
        // code here...
    }
} 

我应该把 [DllImport("Kernel32.dll")] 放在哪里？

Answer 1

你把它放在你从 Kernel32.dll 导入的方法上。

例如，

static class Class    
{
    [DllImport("Kernel32.dll")]
    static extern Boolean Beep(UInt32 frequency, UInt32 duration);

    public static void methodRequiringStuffFromKernel32()
    {
        // code here...
        Beep(...);
    }
}

---

来自@dtb : 请注意，该类应命名为 NativeMethods、SafeNativeMethods 或 UnsafeNativeMethods。参见 Naming Convention for Unmanaged Code Methods了解更多详情。

CA1060: Move P/Invokes to NativeMethods class :

• NativeMethods - This class does not suppress stack walks for unmanaged code permission. (System.Security.SuppressUnmanagedCodeSecurityAttribute must not be applied to this class.) This class is for methods that can be used anywhere because a stack walk will be performed.

• SafeNativeMethods - This class suppresses stack walks for unmanaged code permission. (System.Security.SuppressUnmanagedCodeSecurityAttribute is applied to this class.) This class is for methods that are safe for anyone to call. Callers of these methods are not required to perform a full security review to make sure that the usage is secure because the methods are harmless for any caller.

• UnsafeNativeMethods - This class suppresses stack walks for unmanaged code permission. (System.Security.SuppressUnmanagedCodeSecurityAttribute is applied to this class.) This class is for methods that are potentially dangerous. Any caller of these methods must perform a full security review to make sure that the usage is secure because no stack walk will be performed.