Question

 For Each row As DataRow In dgrFarms.Rows
        Dim sendtroopid As Integer
        sendtroopid = row("idColumn")
        'Do Something
Next

我一直试图在VB.NET中的一列中循环一段时间，我已经完成了我的功课了。当我使用上面的代码时，我得到：

无法将'System.Windows.Forms.DataGridViewRow'类型的对象强制转换为'System.Data.DataRow'。

我看到另一个告诉我的指南：

For Each row As DataGridView In dgrFarms.Rows
        sendtroopid = row("idColumn")
        'Do Something
Next

但这给了我错误：

重载解析失败，因为没有可访问的“Item”接受此数量的参数。

（这是'Row（“idColumn”）上的蓝色下划线）

Answer 1

代码应为：

For Each row As DataGridViewRow In dgrFarms.Rows
    sendtroopid = row.Cells("idColumn").Value
    'Do Something
Next

请注意，每行都是DataGridViewRow，而不是DataGridView。此外，您还可以使用Cells属性从此行获取特定单元格的内容。

Answer 2

这是我在所有应用中使用的功能：

''' <summary>
''' Provides the Properties and Methods to insert each Column from eaqch Row in a Dataset
''' when given a Dataset and a List Box 
''' </summary>
''' <remarks></remarks>
Public Class clsDisplayDataset
    Private mstrClsTitle As String = "clsDisplayDataset"

    ''' <summary>
    ''' For Each Row and Each Column create a single line to be inserted into the 
    ''' List Box
    ''' </summary>
    ''' <param name="idsDataset"></param>
    ''' <param name="ilstListBox"></param>
    ''' <returns>True   -    When successful
    '''          False  -    When unsuccessful</returns>
    ''' <remarks></remarks>
    Public Function DisplayDataSet(ByVal idsDataset As DataSet,
                                   ByRef ilstListBox As ListBox) As Boolean
        Dim lstrRowValue As String = ""
        Try
            For Each ldsRow As DataRow In idsDataset.Tables(0).Rows
                lstrRowValue = ""
                For Each ldsCol As DataColumn In idsDataset.Tables(0).Columns
                    lstrRowValue = lstrRowValue & ldsRow(ldsCol.ColumnName).ToString() & vbTab
                Next
                ilstListBox.Items.Add(lstrRowValue)
            Next
            Return True
        Catch ex As Exception
            DisplayDataSet = False
            Throw New Exception(mstrClsTitle & ".DisplayDataSet" & vbCrLf &
                                "Error Number      [" & Err.Number & vbCrLf &
                                "Error Description [" & Err.Description & "]" & vbCrLf &
                                "Failed to insert columns into List Box")
        End Try
    End Function
End Class

Answer 3

您是否尝试通过检查绑定行的itemType来运行代码？尝试将代码置于：

之间

If (e.Item.ItemType = ListItemType.Item Or e.Item.ItemType = ListItemType.AlternatingItem) Then
'do loop
end if

VB.NET - 循环遍历数据网格中的行的问题

3 个答案: