面向对象的高手请进来，搞了一天了，真不知道问什么？？？谢谢！

[krlin100]

我写了一个类如下：
Public Class _rnfl
Dim dtrn As Double

Public Sub New(ByVal rnfldataset As DataSet, ByVal stcd As String)
Dim crow As DataRow = rnfldataset.Tables("st_rnfl_r").Rows("stcd=" & stcd & "")
dtrn = crow.Item("dtrn")
End Sub
Public Property p() As Double
Get
Return dtrn
End Get
Set(ByVal Value As Double)
dtrn = Value
End Set
End Property
End Class
然后调用他的代码如下：
Dim stcd1 = New _rnfl(rnfldataset, "00001")
TextBox1.Text = stcd1.p
出现的错误如下：
Error: 未将对象引用设置到对象的实例。

请各位指点迷津，谢谢，一定给分！

[visualcpu]

Public Sub New(ByVal rnfldataset As DataSet, ByVal stcd As String)
Dim crow As DataRow = rnfldataset.Tables("st_rnfl_r").Rows("stcd=" & stcd & "")
dtrn = crow.Item("dtrn")
End Sub
改为：

Public Sub _rnfl(ByVal rnfldataset As DataSet, ByVal stcd As String)
Dim crow As DataRow = rnfldataset.Tables("st_rnfl_r").Rows("stcd=" & stcd & "")
dtrn = crow.Item("dtrn")
End Sub

[visualcpu]

或者这样看看！

Public Class _rnfl
Dim dtrn As Double
public sub _rnf1()

end sub

Public Sub New(ByVal rnfldataset As DataSet, ByVal stcd As String)
Dim crow As DataRow = rnfldataset.Tables("st_rnfl_r").Rows("stcd=" & stcd & "")
dtrn = crow.Item("dtrn")
End Sub
Public Property p() As Double
Get
Return dtrn
End Get
Set(ByVal Value As Double)
dtrn = Value
End Set
End Property
End Class
然后调用他的代码如下：
Dim stcd1 = New _rnfl()
strcd1.New(rnfldataset, "00001")
TextBox1.Text = stcd1.p

看看这样行吗？

[krlin100]

不行啊，搂主！

[szch]

Dim stcd1 as Class _rnfl= New _rnfl(rnfldataset, "00001")

[abiho]

呵呵，是这句错了 Dim stcd1 = New _rnfl(rnfldataset, "00001")
应该为 Dim stcd1 as _rnfl = New _rnfl(rnfldataset, "00001")

[krlin100]

还是不行

[maskzha]

Dim stcd1 as Class _rnfl
stcd1=New _rnfl(rnfldataset, "00001")

[maskzha]

Dim stcd1 as _rnfl
stcd1=New _rnfl(rnfldataset, "00001")

[lanbaibai]

Dim stcd1 as New _rnfl(rnfldataset, "00001")

[krlin100]

会不会时我的参数传递有问题？？？

[isage2002]

Dim aa As _rnfl = New _rnfl(rnfldataset, "111111")
问题出现在你得dataset1上，并不是类或类的实现出现问题

[isage2002]

可以通过
rnfldataset.Tables("st_rnfl_r").Rows("stcd=" & stcd & "")
返回row吗？
条件设置在rows里面，我没见过这种用法
:)

[solo108]

用这种方法查datatable里符合条件的数据试试

string strWhere = "dd=" + dd + " and aa=" + aa + " ";
DataRow[] dracc1 = dtAcc.Select(strWhere1);