Question

由于逐行反射相当昂贵，我一直在寻找构建和插入实体的更快的替代方案。我对这个主题进行了一些研究research ，并且还发现了一些性能comparisons，它们似乎表明表达树是可行的方法。我将如何重写以下功能以利用此功能？

    /// <summary>
    /// EVENT HANDLER: Handles the RowDataBound event of the customerSearchResultsGridView control.
    /// 
    /// Allow the entire row to be clicked as a "Selector".
    /// </summary>
    /// <param name="sender">The source of the event.</param>
    /// <param name="e">The <see cref="GridViewRowEventArgs"/> instance containing the event data.</param>
    protected void searchResultsGridView_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            e.Row.Attributes["onclick"] =
                ClientScript.GetPostBackClientHyperlink(searchResultsGridView, "Select$" + e.Row.RowIndex);
        }
    }

    protected void searchResultsGridView_SelectedIndexChanged(object sender, EventArgs e)
    {
        aboutProductBtnPanel.Enabled = (searchResultsGridView.SelectedRow == null) ? false : true;
    }

    /// <summary>
    /// EVENT HANDLER: Handles the PageIndexChanging event of the searchResultsGridView control.
    /// 
    /// Increment the next page of the GridView for results > 15.
    /// </summary>
    /// <param name="sender">The source of the event.</param>
    /// <param name="e">The <see cref="GridViewPageEventArgs"/> instance containing the event data.</param>
    protected void searchResultsGridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        searchResultsGridView.PageIndex = e.NewPageIndex;

        // don't refetch the data, just get it from the session
        searchResultsGridView.DataSource = SessionWrapper.Current.CaptureProductSearchResults;
        searchResultsGridView.DataBind();

        // new page, clear the selection
        searchResultsGridView.SelectedIndex = -1;
        aboutProductBtnPanel.Enabled = false;
    }

编辑：

以下是我最终实施的解决方案：

    public static void InsertTable(IEnumerable<DataTable> chunkedTable)
    {

        Parallel.ForEach(
            chunkedTable,
            new ParallelOptions
            {
                MaxDegreeOfParallelism = Convert.ToInt32(ConfigurationManager.AppSettings["MaxThreads"])
            },
            chunk =>
            {
                Realty_Records_ProdEntities entities = null;
                try
                {
                    entities = new Realty_Records_ProdEntities();
                    entities.Configuration.AutoDetectChangesEnabled = false;

                    foreach (DataRow dr in chunk.Rows)
                    {
                        var parcelToInsert = new Parcel();

                        foreach (DataColumn c in dr.Table.Columns)
                        {
                            var propertyInfo = parcelToInsert.GetType()
                                .GetProperty(
                                    c.ColumnName,
                                    BindingFlags.SetProperty | BindingFlags.IgnoreCase
                                    | BindingFlags.Public | BindingFlags.Instance);

                            propertyInfo?.SetValue(
                                parcelToInsert,
                                TaxDataFunction.ChangeType(
                                    dr[c.ColumnName],
                                    propertyInfo.PropertyType),
                                null);
                        }
                        entities.Parcels.Add(parcelToInsert);
                    }
                    entities.SaveChanges();
                }
                catch (Exception ex)
                {
                    TaxDataError.AddTaxApplicationLog(
                        TaxDataConstant.CategoryError,
                        ex.Source,
                        ex.Message,
                        ex.StackTrace);
                    throw;
                }
                finally
                {
                    entities?.Dispose();
                }
            });
    }

Answer 1

SetProperty(parcelToInsert, c.ColumnName, dr[c.ColumnName])

...用法

{{1}}

从反射切换到表达式树

1 个答案: