diff --git a/Core/InteropServices/GenericSafeHandle.cs b/Core/InteropServices/GenericSafeHandle.cs
index 01fd2937..d5ce24c5 100644
--- a/Core/InteropServices/GenericSafeHandle.cs
+++ b/Core/InteropServices/GenericSafeHandle.cs
@@ -25,7 +25,13 @@ namespace Vanara.InteropServices
 		/// <param name="closeMethod">The delegate method for closing the handle.</param>
 		/// <param name="ownsHandle"><see langword="true"/> to reliably release the handle during the finalization phase; <see langword="false"/> to prevent reliable release (not recommended).</param>
 		/// <exception cref="System.ArgumentNullException">closeMethod</exception>
-		public GenericSafeHandle(IntPtr ptr, Func<IntPtr, bool> closeMethod, bool ownsHandle = true) : base(ownsHandle) => SetHandle(ptr);
+		public GenericSafeHandle(IntPtr ptr, Func<IntPtr, bool> closeMethod, bool ownsHandle = true) : base(ownsHandle)
+		{
+			if (closeMethod == null) throw new ArgumentNullException(nameof(closeMethod));
+
+			SetHandle(ptr);
+			CloseMethod = closeMethod;
+		}
 
 		/// <summary>Gets or sets the close method.</summary>
 		/// <value>The close method.</value>
diff --git a/UnitTests/Core/InteropServices/GenericSafeHandleTests.cs b/UnitTests/Core/InteropServices/GenericSafeHandleTests.cs
index e076fc6d..52935a08 100644
--- a/UnitTests/Core/InteropServices/GenericSafeHandleTests.cs
+++ b/UnitTests/Core/InteropServices/GenericSafeHandleTests.cs
@@ -23,6 +23,55 @@ namespace Vanara.InteropServices.Tests
 			h = new GenericSafeHandle(IntPtr.Zero, p => true);
 			Assert.That(h.IsInvalid);
 		}
+		
+		[Test]
+		public void GenericSafeHandleCloseMethodNull()
+		{
+			Assert.Throws<ArgumentNullException>(() => new GenericSafeHandle((IntPtr)1, null));
+		}
+
+		[Test]
+		public void GenericSafeHandleCloseMethodTest()
+		{
+			var i = 0;
+			using (var h = new GenericSafeHandleWithSetHandle(ptr =>
+			{
+				i = 1;
+				return true;
+			}))
+			{
+				h.SetHandle((IntPtr)1);	
+			}
+
+			Assert.AreEqual(1, i);
+		}
+		
+		
+		private class GenericSafeHandleWithSetHandle : GenericSafeHandle
+		{
+			public GenericSafeHandleWithSetHandle(Func<IntPtr, bool> closeMethod) : base(closeMethod)
+			{}
+
+			public new void SetHandle(IntPtr handle)
+			{
+				base.SetHandle(handle);
+			}
+		}
+
+		[Test]
+		public void GenericSafeHandleCloseMethodWithHandleTest()
+		{
+			var i = 0;
+			using (new GenericSafeHandle((IntPtr)1, ptr =>
+			{
+				i = 1;
+				return true;
+			}))
+			{
+			}
+
+			Assert.AreEqual(1, i);
+		}
 
 		[Test]
 		public void GenericSafeHandleTest1()