如何在列表中添加结构类型对象或从列表中检索结构类型对象? [英] How do I add and retrieve a structure type object to/from a list?

问题描述

如何在列表中添加结构类型对象或从列表中检索结构类型对象.只有最后写入的值似乎是可检索的. VS2005中的部分样本.实验代码，仅检索最后写入的值.

How do I add and retrieve a structure type object to/from a list. Only the last value written seems to be retrieveable. Partial sample in VS2005. Experimental code which only retrieves the last value written.

While (Not datainfile.EndOfStream And i < pk_size)
 With pk_set
  .profile = datainfile.ReadLine '.profile = code(datainfile.ReadLine, myPWD)
  .UID = datainfile.ReadLine '.UID = code(datainfile.ReadLine, myPWD)
  .PWD = datainfile.ReadLine '.PWD = code(datainfile.ReadLine, myPWD)
  .URL = datainfile.ReadLine '.URL = code(datainfile.ReadLine, myPWD)
  j = lstprofiles.Items.Add(.profile) 'profileIdx.Add(.profile) <-- not needed?
  End With
  pkList.Add(pk_set) '<-----<<this increment isn't occurring
  With pkList(i)
  MsgBox("wrote to pkList: index = " & j & ", " & _
                           "count = " & pkList.Count & ", " & _
                            .profile & ", " & .UID & ", " & .PWD & ", " & .URL)
 End With

 ''''With lstprofiles.Items(j) 'was first i-1 then i
 '''' Dim lItemToString As String = .ToString
 '''' MsgBox("read from lstprofiles: index = " & j & ", " & _
 ''''                            lItemToString & " AKA " & lstprofiles.Items(j))
 ''''End With
 i += 1
End While

For i = 0 To 8 'This iterated
 ''''With lstprofiles.Items(i) 'was i-1
 '''' Dim lItemToString As String = .ToString
 '''' MsgBox("read from lstProfiles: position index = " & i & ", |" & lItemToString & "|")
 ''''End With
 ''''MsgBox("lstProfiles.items(" & i & ") = " & lstprofiles.Items(i))
'With pkList(i) ''With pkList.Item(i + 1)
 MsgBox("pkList(" & i & ") = " & pkList(i).ToString & _
        " Profile = " & pkList(i).profile & _
        " UID = " & pkList(i).UID & _
        " PWD = " & pkList(i).PWD & _
        " URL = " & pkList(i).URL)
'End With

Next



For Each pkpr_set In pkList 'this contains the object's last value only,
                            'for all values of each
 With pkpr_set
 MsgBox("pkpr's profile is " & .profile & " and it contains " _
                      & .UID & ", " _
                      & .PWD & ", " _
                      & .URL)
 End With
Next

推荐答案

pk_set变量始终是同一对象.您只需在每次迭代中更改其属性.因此，当执行pkList.Add(pk_set)行时，它只是将对同一对象的另一个引用添加到列表中.要解决此问题，请在第一个With pk_set之前添加新行，如下所示:

The pk_set variable is always the same object. You are just changing its properties with each iteration. So when the pkList.Add(pk_set) line is executed it is just adding another reference to the same object to the list. To fix this, add a new line before the first With pk_set that looks something like this:

pk_set = New <whatever type pk_set is>()

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