The .NET PictureBox control doesn’t expose this property and you must manually resize the image. Notice that, if AutoSize is True and you are assigning an image in Metafile format, you can reproduce the VB6 behavior by assigning the Image to the BackgroundImage property and by assigning ImageLayout.Stretch to the BackgroundImageLayout property.

VB Migration Partner fully supports this property. No manual adjustments of other properties are necessary.