dotnet/winforms

Icon.Save(stream) each time returns different results

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#8,853 opened on Dec 2, 2021

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area-System.Drawinghelp wanted

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Description

Description

We use the following code to compare two icons:

private static bool IconEquals(Icon icon1, Icon icon2) {
                var stream1 = new System.IO.MemoryStream();
                icon1.Save(stream1);
                var stream2 = new System.IO.MemoryStream();
                icon2.Save(stream2);
                return System.Linq.Enumerable.SequenceEqual(stream1.ToArray(), stream2.ToArray());
        }

With the net6.0 release the stream.ToArray() method each time returns different results for the same Icon. You can modify the IconEquals as follows and it will return false:

private static bool IconEquals(Icon icon1) {
                var stream1 = new System.IO.MemoryStream();
                icon1.Save(stream1);
                var stream2 = new System.IO.MemoryStream();
                icon1.Save(stream2);
                return System.Linq.Enumerable.SequenceEqual(stream1.ToArray(), stream2.ToArray());
        }

Reproduction Steps

Launch the following code with any Icon:

private static bool IconEquals(Icon icon1) {
                var stream1 = new System.IO.MemoryStream();
                icon1.Save(stream1);
                var stream2 = new System.IO.MemoryStream();
                icon1.Save(stream2);
                return System.Linq.Enumerable.SequenceEqual(stream1.ToArray(), stream2.ToArray());
        }

Expected behavior

The IconEquals method should return true.

Actual behavior

The IconEquals method returns false.

Regression?

Works on net5.0

Known Workarounds

No response

Configuration

Windows 10

Other information

No response

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