所有我想做的是检查一个对象是否为null，但无论我做什么，如果它编译，它抛出一个NullReferenceException只是试图检查！这里是我做了：
原文链接：https://www.f2er.com/vb/256346.htmlIf ((Not (comp.Container Is Nothing)) And (Not (comp.Container.Components Is Nothing))) Then
For i As Integer = 0 To comp.Container.Components.Count() - 1 Step 1
fixUIIn(comp.Container.Components.Item(i),style)
Next
End If
If ((Not IsDBNull(comp.Container)) And (Not IsDBNull(comp.Container.Components))) Then
For i As Integer = 0 To comp.Container.Components.Count() - 1 Step 1
fixUIIn(comp.Container.Components.Item(i),style)
Next
End If
If ((Not IsNothing(comp.Container)) And (Not IsNothing(comp.Container.Components))) Then
For i As Integer = 0 To comp.Container.Components.Count() - 1 Step 1
fixUIIn(comp.Container.Components.Item(i),style)
Next
End If
If ((Not (comp.Container Is DBNull.Value)) And (Not (comp.Container.Components Is DBNull.Value))) Then
For i As Integer = 0 To comp.Container.Components.Count() Step 1
fixUIIn(comp.Container.Components.Item(i),style)
Next
End If
我看过VB书，搜索几个论坛，和一切应该工作不是！对不起，问这样的补救问题，但我只是需要知道。
只是这样你知道，调试器说，null对象是comp.Container