将listbox转换为DataGridView

Question

我希望从listbox更改为DataGridView。

在列表框中，我可以查看数据，并使用view/download varbinary选择项目

我能用DataGridView做同样的事情吗？

Dim cmd As SqlCommand
Dim adapter As SqlDataAdapter
Dim ofd As New OpenFileDialog
Dim Dt As New DataTable


Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    Try


        adapter = New SqlDataAdapter("select ID, Label + Extension as 'FileName', [Filesys] from TBL_FILES", sqlcon)

        adapter.Fill(Dt)

        Me.ListBox1.DataSource = Dt
        Me.ListBox1.DisplayMember = "FileName"

        Me.ListBox1.ValueMember = "ID"

        Me.Dt.Constraints.Add("Primary", Dt.Columns("ID"), True)

    Catch ex As Exception

    End Try

End Sub
  Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.SelectedIndexChanged
    Try
        Dim FileName As String = Me.ListBox1.Text
        Dim row As DataRow = Dt.Rows.Find(ListBox1.SelectedValue)
        Dim file_data() As Byte = CType(row(2), Byte())
        Dim fs As New FileStream(FileName, FileMode.OpenOrCreate, FileAccess.Write)

        fs.Write(file_data, 0, file_data.Length)
        Process.Start(FileName)
    Catch ex As Exception

    End Try
End Sub

        ofd.Filter = "All File (*.*) |*.*"

        If ofd.ShowDialog = DialogResult.OK Then
            Label1.Text = ofd.FileName
        End If
    Catch ex As Exception

    End Try
End Sub

Private Sub Button1_Click（sender作为Object,e作为EventArgs）处理Button1.Click

    Try


        cmd = New SqlCommand("Insert into TBL_FILES (Label, Filesys,Extension) values (@Label, @Filesys, @Extension)", sqlcon)

        sqlcon.Open()

        cmd.Parameters.Add(New SqlParameter("@Label", SqlDbType.NVarChar, 50)).Value = TextBox1.Text
        cmd.Parameters.Add(New SqlParameter("@Extension", SqlDbType.NVarChar, 50)).Value = TextBox1.Text

        Dim fs As New FileStream(ofd.FileName, FileMode.Open, FileAccess.Read)

        Dim br As New BinaryReader(fs)

        Dim file() As Byte = br.ReadBytes(br.BaseStream.Length)

        cmd.Parameters.Add(New SqlParameter("Filesys", SqlDbType.VarBinary)).Value = file

        cmd.ExecuteNonQuery()

        sqlcon.Close()

        MsgBox(" file saved ", MsgBoxStyle.Information, "info")

    Catch ex As Exception

    End Try
End Sub

Answer 1

根据评论和您的回复，您似乎选择了尝试使用DataGridView...下面是一些有用的代码来使用这些。

注意：我将假设您正在使用一个简单的sqlCommand获取数据，如果不是忽略其中的“com”部分，因为我包含它只是为了向您展示如何工作的流程。注意：在重复使用之前清除数据集是一个好主意，以确保清除了旧数据。

您可能还想考虑将对象重命名为更合适的对象，如“dstblfiles”和“gvtblfiles”。

Dim adapter as New SqlDataAdapter()

TBL_FILES.Clear()
adapter.SelectCommand = com
adapter.Fill(TBL_FILES)

TBL_FILESDataGridView.DataSource = TBL_FILES.Tables(0)
TBL_FILESDataGridView.DataBind()

adapter = Nothing