Breadcrumbs

[MrAksel]

To view various property items for an image, you can use the Image.PropertyItems to list every item available. One example could be

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For Each Item As PropertyItem In MyImage.PropertyItems
   MessageBox.Show(Item.Id & ": " & Item.Len & " bytes value.")
Next

There is a Value property for the PropertyItem structure, it is a byte array that contains the actual value. You can use the Type property together with the Value to get the actual value.

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Private Function GetValue(prop As PropertyItem) As Object
	Select Case prop.Type
		Case 1
			Return prop.Value(0)
		Case 2
			Return System.Text.Encoding.ASCII.GetString(prop.Value)
		Case 3
			Return BitConverter.ToUInt16(prop.Value, 0)
		Case 4
			Return BitConverter.ToUInt32(prop.Value, 0)
		Case 5
			Return New UInteger() {BitConverter.ToUInt32(prop.Value, 0), BitConverter.ToUInt32(prop.Value, 4)} 'URational class is not supported by .NET'
		Case 6
			Return CSByte(prop.Value(0))
		Case 7
			Return prop.Value(0) 'Undefined'
		Case 8
			Return BitConverter.ToInt16(prop.Value, 0)
		Case 9
			Return BitConverter.ToInt32(prop.Value, 0)
		Case 10
			Return New Integer() {BitConverter.ToInt32(prop.Value, 0), BitConverter.ToInt32(prop.Value, 4)} 'Rational class is not supported by .NET'
		Case 11
			Return BitConverter.ToSingle(prop.Value, 0)
		Case 12
			Return BitConverter.ToDouble(prop.Value, 0)
	End Select
	Return prop.Value
End Function

Then we can edit our first function to show the actual value too:

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For Each Item As PropertyItem In MyImage.PropertyItems
   MessageBox.Show(Item.Id & ": " & GetValue(Item).ToString())
Next