如何刷新dataGridView

Question

在Insert或Update之后刷新DataGridView控件时遇到问题。源代码：

从datatable中的表中获取所有行，并将其设置为数据源：

Dim dt1 as DataTable = GetData("SELECT * FROM CLAIMSTATE ")
dataGrid.DataSource = dt1

如果ID有值，则更新事件，如果没有值，则插入：

Private Sub dataGrid_RowLeave(ByVal sender As System.Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles dataGrid.RowLeave
Dim row As DataGridViewRow = CType(sender, DataGridView).Rows(e.RowIndex)
  Dim query As New StringBuilder("")
  If row.Cells(0).Value & "" = "" Then
    query.Append("INSERT INTO CLAIMSTATE ")
    query.Append("(CST_CODE, CST_LABEL, CST_POINTS)")
    query.Append("VALUES ")
    query.Append("(?, ?, ?)")
  Else
    query.Append("Update CLAIMSTATE ")
    query.Append("SET CST_CODE = ?, ")
    query.Append("CST_LABEL = ?, ")
    query.Append("CST_POINTS = ? ")
    query.Append("WHERE CST_ID = ? ")
  End If
  Dim command As New OdbcCommand(query.ToString(), con)
  command.Parameters.Add("@cst_code", OdbcType.Char).Value = row.Cells(1).Value
  command.Parameters.Add("@cst_label", OdbcType.NVarChar).Value = row.Cells(2).Value
  command.Parameters.Add("@cst_points", OdbcType.Decimal).Value = row.Cells(3).Value
  command.Parameters.Add("@cst_id", OdbcType.BigInt).Value = row.Cells(0).Value
  Dim res As Integer = ExecuteNonQuery(command)
End Sub
Public Function GetData(ByRef sqlQuery As String) As DataTable
    Dim command As New OdbcCommand(sqlQuery, con)
    Try
      If con.State = ConnectionState.Closed Then
        con.ConnectionString = conString
        con.Open()
      End If
      Using dr As OdbcDataReader = command.ExecuteReader()
        Dim dt As New DataTable()
        dt.Load(dr)
        Return dt
      End Using
      'con.Close()
    Catch ex As Exception
      MsgBox(ex.Message)
      con.Close()
      Return Null
    End Try
  End Function
Public Function ExecuteNonQuery(ByRef command As OdbcCommand) As Integer
Dim result As Integer = 0
If con.State = ConnectionState.Closed Then
  con.ConnectionString = conString
  con.Open()
End If
'Dim command As New OdbcCommand(sqlQuery, conn)
Try
  'command.Connection = con
  'Dim cmd As New OdbcCommand( sqlQuery, conn)
  result = command.ExecuteNonQuery()
Catch
  result = 0
  If con IsNot Nothing Then
    con.Close()
    command.Dispose()
  End If
Finally
  command.Dispose()
End Try
Return result
End Function

我试图从表中获取所有记录，并在方法结束时再次设置数据源，但没有成功。

如果我把代码：

dataGrid.Rows.Clear()
dataGrid.Columns.Clear()
dt1 = GetData("SELECT * FROM CLAIMSTATE ")
dataGrid.DataSource = dt1

在事件方法RowLeave结束时，我收到了以下错误：

"操作无效，因为它导致对SetCurrentCellAddressCore函数"

在dataGrid.Rows.Clear（）上，但如果我删除行代码Rows.Clear（）和Columns.Clear！

请帮帮我！

Answer 1

这里有一个C#类，我用它来连接搜索我的GridView。我想你需要的应该是相似的。

    protected void lbSearch_Click(object sender, EventArgs e)
    {
        if (txtSearch.Text.Trim().Length > 0)
        {
            odsInbox.FilterExpression =
                string.Format("(l_name LIKE '*{0}*') OR (f_name LIKE '*{0}*') OR (title LIKE '*{0}*')",
                txtSearch.Text);
        }
        else
        {
            odsInbox.FilterExpression = string.Empty;
        }
        gvInbox.DataBind();
    }
    protected void lbClear_Click(object sender, EventArgs e)
    {
        odsInbox.FilterExpression = string.Empty;
        txtSearch.Text = "";
        gvInbox.DataBind();
    }

我希望这能让你走上正轨。

Answer 2

为了解决这个问题，我使用了OdbcDataAdapter。我用适配器保存所有更改。更新（dataTable），在我再次填充数据表之后：adapter.fill（dataTable）.