'宣言 Public MustOverride Function GetContext() As C1DocumentSourceContext
'使用法 Dim instance As C1DocumentSource Dim value As C1DocumentSourceContext value = instance.GetContext()
public abstract C1DocumentSourceContext GetContext()
'宣言 Public MustOverride Function GetContext() As C1DocumentSourceContext
'使用法 Dim instance As C1DocumentSource Dim value As C1DocumentSourceContext value = instance.GetContext()
public abstract C1DocumentSourceContext GetContext()