没问题 [英] Is Nothing problem
问题描述
您好,
我有一个通用列表如下:
Dim rows As New Generic.List(Of row)
现在我有一行:
Dim myRow作为行
我试图检查,在我的代码中,如果行是没有:
如果myRow什么都没有那么
....
结束如果
我得到错误:
" Is"需要具有引用类型的操作数,但是这个操作数有一个Rows的值。
我知道我做错了什么?
无论如何,这是我的行定义及其依赖关系:
''行
公共结构行
'' - [属性] ----
''单元格
私有_Cells As Generic.List(Of Cell)
Public Property Cells()As Generic.List(Of Cell)
获取
返回_Cells
结束获取
设置(ByVal Cells As Generic.List(Of Cell))
_Cells = Cells
结束集
结束属性''单元格
''名称
私有_Name为字符串
公共属性名称()为字符串
获取
返回_Name
结束获取
设置(ByVal名称为字符串)
_Name =姓名
结束集
结束物业''名称
结构结构''行>
''细胞
公共结构细胞
'' - [属性] ----
''内容
私有_Content As Object
公共财产内容()作为对象
获取
返回_内容
结束获取
设置(ByVal内容为对象)
_Content = Content
结束集
结束物业''内容
''文化
私人_文化作为CultureInfo
公共财产文化()作为CultureInfo
获取
返回_Culture
结束获取
Set(ByVal Culture As CultureInfo)
_Culture =文化
结束集
结束物业''文化
结束结构''细胞
谢谢,
Miguel
Hello,
I have a generic list as follows:
Dim rows As New Generic.List(Of row)
Now I have a row:
Dim myRow As row
I tried to check, further in my code, if the row is nothing:
If myRow Is Nothing Then
....
End If
I get an error:
"Is" requires operand that have reference types but this operand has
the value of Rows.Row"
Any idea what I am doing wrong?
Anyway, this is my row definition and its dependencies:
'' Row
Public Structure Row
'' -- [Properties] ----
'' Cells
Private _Cells As Generic.List(Of Cell)
Public Property Cells() As Generic.List(Of Cell)
Get
Return _Cells
End Get
Set(ByVal Cells As Generic.List(Of Cell))
_Cells = Cells
End Set
End Property '' Cells
'' Name
Private _Name As String
Public Property Name() As String
Get
Return _Name
End Get
Set(ByVal Name As String)
_Name = Name
End Set
End Property '' Name
End Structure '' Row
'' Cell
Public Structure Cell
'' -- [Properties] ----
'' Content
Private _Content As Object
Public Property Content() As Object
Get
Return _Content
End Get
Set(ByVal Content As Object)
_Content = Content
End Set
End Property '' Content
'' Culture
Private _Culture As CultureInfo
Public Property Culture() As CultureInfo
Get
Return _Culture
End Get
Set(ByVal Culture As CultureInfo)
_Culture = Culture
End Set
End Property '' Culture
End Structure '' Cell
Thanks,
Miguel
推荐答案
结构是值类型,因此您可以使用= Nothing。
-
David Anton
www.tangiblesoftwaresolutions.com
即时C#:VB转换为C#转换器
即时VB:C#到VB转换器
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" shapper"写道:
Structures are value types, so you can use "= Nothing".
--
David Anton
www.tangiblesoftwaresolutions.com
Instant C#: VB to C# converter
Instant VB: C# to VB converter
Instant C++: C#/VB to C++ converter
Instant Python: C#/VB to Python converter
"shapper" wrote:
你好,
我有一个通用列表如下:
昏暗的行As New Generic.List(排)
现在我有一排:
Dim myRow As row
我试着在我的代码中进一步查看行是否为空:
如果myRow什么都没有那么
....
结束如果
我收到错误:
" Is"需要具有引用类型的操作数,但是这个操作数有一个Rows的值。
我知道我做错了什么?
无论如何,这是我的行定义及其依赖关系:
''行
公共结构行
'' - [属性] ----
''单元格
私有_Cells As Generic.List(Of Cell)
Public Property Cells()As Generic.List(Of Cell)
获取
返回_Cells
结束获取
设置(ByVal Cells As Generic.List(Of Cell))
_Cells = Cells
结束集
结束属性''单元格
''名称
私有_Name为字符串
公共属性名称()为字符串
获取
返回_Name
结束获取
设置(ByVal名称A s String)
_Name =姓名
结束集
结束物业''名称
结束结构''行
''单元格
公共结构单元
'' - [属性] - ---
''内容
私有_Content As Object
公共财产内容()作为对象
获取
返回_内容
结束获取
设置(ByVal内容为对象)
_Content = Content
结束套装
结束物业''内容
''文化
私人_文化作为CultureInfo
公共物业文化()作为CultureInfo
获取
返回_Culture
结束获取
套装(ByVal Culture As CultureInfo)
_Culture = Culture
结束集
结束物业''文化
结束结构''单元格
谢谢,
Miguel
Hello,
I have a generic list as follows:
Dim rows As New Generic.List(Of row)
Now I have a row:
Dim myRow As row
I tried to check, further in my code, if the row is nothing:
If myRow Is Nothing Then
....
End If
I get an error:
"Is" requires operand that have reference types but this operand has
the value of Rows.Row"
Any idea what I am doing wrong?
Anyway, this is my row definition and its dependencies:
'' Row
Public Structure Row
'' -- [Properties] ----
'' Cells
Private _Cells As Generic.List(Of Cell)
Public Property Cells() As Generic.List(Of Cell)
Get
Return _Cells
End Get
Set(ByVal Cells As Generic.List(Of Cell))
_Cells = Cells
End Set
End Property '' Cells
'' Name
Private _Name As String
Public Property Name() As String
Get
Return _Name
End Get
Set(ByVal Name As String)
_Name = Name
End Set
End Property '' Name
End Structure '' Row
'' Cell
Public Structure Cell
'' -- [Properties] ----
'' Content
Private _Content As Object
Public Property Content() As Object
Get
Return _Content
End Get
Set(ByVal Content As Object)
_Content = Content
End Set
End Property '' Content
'' Culture
Private _Culture As CultureInfo
Public Property Culture() As CultureInfo
Get
Return _Culture
End Get
Set(ByVal Culture As CultureInfo)
_Culture = Culture
End Set
End Property '' Culture
End Structure '' Cell
Thanks,
Miguel
" shapper" < md ***** @ gmail.com写信息
news:11 ********************** @ n33g2000cwc。 googlegr oups.com ...
"shapper" <md*****@gmail.comwrote in message
news:11**********************@n33g2000cwc.googlegr oups.com...
如果myRow为Nothing那么
If myRow Is Nothing Then
如果myRow = Nothing Then
If myRow = Nothing Then
实际上,= Nothing除非你的结构中超过''=''运算符
,否则不会工作。
-
David Anton
www.tangiblesoftwaresolutions.com
即时C#:VB到C#转换器
即时VB:C#到VB转换器
即时C ++:C#/ VB到C ++转换器
即时Python:C#/ VB到Python转换器
" shapper"写道:
Actually, "= Nothing" won''t work unless you have overloaded the ''='' operator
in your structure.
--
David Anton
www.tangiblesoftwaresolutions.com
Instant C#: VB to C# converter
Instant VB: C# to VB converter
Instant C++: C#/VB to C++ converter
Instant Python: C#/VB to Python converter
"shapper" wrote:
你好,
我有一个通用列表如下:
昏暗的行As New Generic.List(排)
现在我有一排:
Dim myRow As row
我试着在我的代码中进一步查看行是否为空:
如果myRow什么都没有那么
....
结束如果
我收到错误:
" Is"需要具有引用类型的操作数,但是这个操作数有一个Rows的值。
我知道我做错了什么?
无论如何,这是我的行定义及其依赖关系:
''行
公共结构行
'' - [属性] ----
''单元格
私有_Cells As Generic.List(Of Cell)
Public Property Cells()As Generic.List(Of Cell)
获取
返回_Cells
结束获取
设置(ByVal Cells As Generic.List(Of Cell))
_Cells = Cells
结束集
结束属性''单元格
''名称
私有_Name为字符串
公共属性名称()为字符串
获取
返回_Name
结束获取
设置(ByVal名称A s String)
_Name =姓名
结束集
结束物业''名称
结束结构''行
''单元格
公共结构单元
'' - [属性] - ---
''内容
私有_Content As Object
公共财产内容()作为对象
获取
返回_内容
结束获取
设置(ByVal内容为对象)
_Content = Content
结束套装
结束物业''内容
''文化
私人_文化作为CultureInfo
公共物业文化()作为CultureInfo
获取
返回_Culture
结束获取
套装(ByVal Culture As CultureInfo)
_Culture = Culture
结束集
结束物业''文化
结束结构''单元格
谢谢,
Miguel
Hello,
I have a generic list as follows:
Dim rows As New Generic.List(Of row)
Now I have a row:
Dim myRow As row
I tried to check, further in my code, if the row is nothing:
If myRow Is Nothing Then
....
End If
I get an error:
"Is" requires operand that have reference types but this operand has
the value of Rows.Row"
Any idea what I am doing wrong?
Anyway, this is my row definition and its dependencies:
'' Row
Public Structure Row
'' -- [Properties] ----
'' Cells
Private _Cells As Generic.List(Of Cell)
Public Property Cells() As Generic.List(Of Cell)
Get
Return _Cells
End Get
Set(ByVal Cells As Generic.List(Of Cell))
_Cells = Cells
End Set
End Property '' Cells
'' Name
Private _Name As String
Public Property Name() As String
Get
Return _Name
End Get
Set(ByVal Name As String)
_Name = Name
End Set
End Property '' Name
End Structure '' Row
'' Cell
Public Structure Cell
'' -- [Properties] ----
'' Content
Private _Content As Object
Public Property Content() As Object
Get
Return _Content
End Get
Set(ByVal Content As Object)
_Content = Content
End Set
End Property '' Content
'' Culture
Private _Culture As CultureInfo
Public Property Culture() As CultureInfo
Get
Return _Culture
End Get
Set(ByVal Culture As CultureInfo)
_Culture = Culture
End Set
End Property '' Culture
End Structure '' Cell
Thanks,
Miguel
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