1

我想选择数据集中的所有列。数据集是从数据库表中检索的。

这是我的代码：

  lstvCustomers.Items.Clear()
    Dim result = (From cust In dsCust.Tables(0).AsEnumerable).ToList
    'When i set where clause condition (Where cust.Field(Of String)("Ccd").Contains(txtCustID.Text))
    ' error occured in bellow line Error : The source contains not datarow
    Dim custTable As DataTable = result.CopyToDataTable
    lstvCustomers.Columns.Clear()
    For cls As Integer = 1 To custTable.Columns.Count - 1
        lstvCustomers.Columns.Add("COl - " & cls)
    Next

    Dim i As Integer = 0
    For Each row In custTable.Rows
        Dim lst As ListViewItem = lstvCustomers.Items.Add(row(0))
        For cls As Integer = 1 To custTable.Columns.Count - 1
            lst.SubItems.Add(row(cls))
        Next
        i = i + 1
    Next

输出
Col1 COl2 COl3 COL4 Col5 COl6 COL7
Cust101 Cust101 True Cust101 Cust101 Cust101 232323
Cust102 Cust102 True Cust102 Cust102 Cust102 234324

我想从数据集中选择所有列。帮我。

4

3 回答 3

1

尝试：

    Dim qry = (From cust In custTable.AsEnumerable
                Where cust.Field(Of String)("Ccd").Contains(txtResults.Text)
                Select cust).ToList

这将返回与条件匹配的每个数据行作为数据行列表，您可以在其中根据需要访问每个字段。

要将行添加到列表视图，请尝试以下操作：

For Each row In qry
    lstvCustomers.Items.Add(row.Field(Of String)("Ccd")).SubItems.Add(row.Field(Of String)("Cnm"))
Next
于 2013-11-11T17:50:37.097 回答
0 
lstvCustomers.Items.Clear()  
Dim result = (From cust In dsCust.Tables(0).Select("Ccd LIKE '%" & txtCustID.Text & "%'")).ToList  
Dim clm As Integer = 0  
For Each row As DataRow In result  
    lstvCustomers.Items.Add(row(0))  
    lstvCustomers.Items(clm).SubItems.Add(row(1))  
    clm = clm + 1  
Next
于 2013-11-12T15:43:49.017 回答
0

我搜索了很多（好吧，超过四个谷歌搜索）以寻找解决方案，最后我最终（上图）收集到 LINQ 不会删除 - 所以你使用 LINQ 来选择你想要摆脱的行通过正在使用的数据库技术的“常规”机制删除和删除它们。似乎让所有关于 LINQ 的与数据库无关的宣传变得非常愚蠢？这个至少可以工作，尽管我会玩弄两个“For Each”循环，看看我是否可以将它减少到一个。我有一个属性表，我想在其中删除具有选定属性名称（第三个键域）的对象类型（第一个键域）的所有条目，我想出了这个。仅供参考，REPLY 对象有点像 Error 对象 - 我只是打包错误消息，

  ' <summary>
  ' The user has decided they don't want a particular property type so we delete all
  ' properties of that type in the table - belonging to any object of that ObjectType
  ' </summary>
  ' <param name="sObjectType"></param>
  ' <param name="sName"></param>
  ' <returns></returns>
  ' <remarks></remarks>
  Public Function DeleteAllPropsByName(sObjectType As String, sName As String) As Reply

    DeleteAllPropsByName = New Reply(True)

    Dim T As DataTable = mDB.DataTableImage(msTableName)
    Dim q = From rw In T.AsEnumerable
            Where rw.Field(Of String)("ObjectType") = sObjectType _
            And rw.Field(Of String)("PropName") = sName

    ' Somewhere to remember our list of target rows to delete
    Dim rows As New List(Of DataRow)

    For Each row In q
      '
      ' LINQ doesn't delete so we need to delete from the Datatable directly.
      ' If we delete here we get the collection modified error so we have to save 
      ' the datarows to ANOTHER list and then delete them from there.
      rows.Add(row)

    Next

    For Each rw As DataRow In rows
      '
      ' Call the Delete routine in my table class passing it the 
      ' primary key of the row to delete
      '
      DeleteAllPropsByName = gDB.Table(msTableName).Delete( _
                                  rw.Item("ObjectType").ToString, _
                                  CInt(rw.Item("ObjectID")), _
                                  rw.Item("PropName").ToString)

      If Not DeleteAllPropsByName.OK Then
        ' The reply object (in DeleteAllPropsByName) has all the error info so we can just
        ' exit and return it if the delete failed.
        Exit Function
      End If

    Next

  End Function
于 2018-01-09T02:33:57.013 回答