使用 DataTable 和 Linq 导出到 Excel 中缺少某些数据
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【中文标题】使用 DataTable 和 Linq 导出到 Excel 中缺少某些数据【英文标题】：Some data is missing in the Export to Excel using DataTable and Linq 【发布时间】：2016-05-04 01:57:22 【问题描述】：我在单个 XL 文件中导出三个工作表，但我在第二个 DataTable（Education Details 表）和第三个 DataTable（Employeement Details 表）中缺少一些用户数据。
Education Details 表是一些用户不存在，但用户正在显示的Employeement Details 表。用户电子邮件 ID 是否存在所有三个数据库表。
DataSe ds = new DataSet();
DataTable dt = new DataTable("Registration Details");
DataTable dt1 = new DataTable("Education Details");
DataTable dt2 = new DataTable("Employeement Details");
dt = bl.Get_Registrationdetailsbydate(bo);
gv_Regdetails.DataSource = dt;
gv_Regdetails.DataBind();
dt1 = bl.Get_Registrationdetailsbydate1(bo);
dt2 = bl.Get_Registrationdetailsbydate2(bo);
DataTable filteredEducation = dt1.AsEnumerable()
.Where(x => dt.AsEnumerable()
.Any(z => z.Field<string>("Email").Trim() == x.Field<string>("Email").Trim()))
.CopyToDataTable();
DataTable filteredEmployee = dt2.AsEnumerable()
.Where(x => dt.AsEnumerable()
.Any(z => z.Field<string>("Email").Trim() == x.Field<string>("Email").Trim()))
.CopyToDataTable();
dt.TableName = "Registration Details";
filteredEducation.TableName = "Education Details";
filteredEmployee.TableName = "Employeement Details";
ds.Tables.Add(dt);
ds.Tables.Add(filteredEducation);
ds.Tables.Add(filteredEmployee);
ExcelHelper.ToExcel(ds, "DangoteUsers.xls", Page.Response);
我的结果基于第一个DataTable 用户Email，然后根据第一个DataTable Email id 填写第二个DataTable 详细用户。与Employment Details 相同。第一个DataTable 和第二个DataTable 中的问题。我也不会返回DataTable。
我推荐this example
【问题讨论】：
区分大小写的字符串比较和表格之间的电子邮件地址格式不一样？ 您的 ToExcel() 库是 8 年前的。如果您使用我的（免费）C# 库，您可能想看看会发生什么。它只需要一行代码（只需将您的数据集和文件名传递给它），它将使用 OpenXML 库创建一个真正的 Excel .xlsx 文件。 mikesknowledgebase.com/pages/CSharp/ExportToExcel.htm 【参考方案1】：问题出在文章中从DataSet转换为Excel的解决方案中。使用这种自制转换不是一个好主意。使用Jet/ACE engine 或Microsoft Office Interop。至少他们保证，他们没有这种错误，将来可能会变得更多。更好地使用已经被社区高度接受的东西。在这里，我写了一个如何使用Interop 的方法。
首先您需要添加对Microsoft.Office.Interop.Excel 的引用。下面是如何做到这一点，取自msdn article
添加 Excel 程序集作为对项目的引用：右键单击 项目，选择添加引用。
单击“添加引用”对话框的 COM 选项卡，找到 Microsoft Excel 11 对象库。
双击 Microsoft Excel 11 对象库，然后 按确定。
显然，如果您有更大版本的 Excel 11，请使用它。
这里是代码，它的工作流程有 cmets/regions。您应该使用using Excel = Microsoft.Office.Interop.Excel; 作为参考
public void ExcelBtn_Click(object sender, EventArgs e)
DataSet dst = PrepareData();
byte[] bytes = ExportDataSetToExcel(dst);
Response.ClearContent();
Response.ContentType = "application/msoffice";
Response.AddHeader("Content-Disposition", @"attachment; filename=""ExportedExcel.xlsx"" ");
Response.BinaryWrite(bytes);
Response.End();
public static DataSet PrepareData()
DataTable badBoysDst = new DataTable("BadBoys");
badBoysDst.Columns.Add("Nr");
badBoysDst.Columns.Add("Name");
badBoysDst.Rows.Add(1, "Me");
badBoysDst.Rows.Add(2, "You");
badBoysDst.Rows.Add(3, "Pepe");
badBoysDst.Rows.Add(4, "Roni");
//Create a Department Table
DataTable goodBoysDst = new DataTable("GoodBoys");
goodBoysDst.Columns.Add("Nr");
goodBoysDst.Columns.Add("Name");
goodBoysDst.Rows.Add("1", "Not me");
goodBoysDst.Rows.Add("2", "Not you");
goodBoysDst.Rows.Add("3", "Quattro");
goodBoysDst.Rows.Add("4", "Stagioni");
DataTable goodBoysDst2 = new DataTable("GoodBoys2");
goodBoysDst2.Columns.Add("Nr");
goodBoysDst2.Columns.Add("Name");
goodBoysDst2.Rows.Add("1", "Not me");
goodBoysDst2.Rows.Add("2", "Not you");
goodBoysDst2.Rows.Add("3", "Quattro");
goodBoysDst2.Rows.Add("4", "Stagioni");
DataTable goodBoysDst3 = new DataTable("GoodBoys3");
goodBoysDst3.Columns.Add("Nr");
goodBoysDst3.Columns.Add("Name");
goodBoysDst3.Rows.Add("1", "Not me");
goodBoysDst3.Rows.Add("2", "Not you");
goodBoysDst3.Rows.Add("3", "Quattro");
goodBoysDst3.Rows.Add("4", "Stagioni");
//Create a DataSet with the existing DataTables
DataSet dst = new DataSet("SchoolBoys");
dst.Tables.Add(badBoysDst);
dst.Tables.Add(goodBoysDst);
dst.Tables.Add(goodBoysDst2);
dst.Tables.Add(goodBoysDst3);
return dst;
public static byte[] ExportDataSetToExcel(DataSet dst)
#region Create The Excel
Excel.Application excelApp = null;
Excel.Workbook excelWorkBook = null;
try
excelApp = new Excel.Application();
if (excelApp == null)
throw new Exception("You can throw custom exception here too");
excelWorkBook = excelApp.Workbooks.Add();
int sheetNr = 1;
foreach (DataTable table in dst.Tables)
Excel.Worksheet excelWorkSheet = null;
//Add a new worksheet or reuse first 3 sheets of workbook with the Datatable name
if (sheetNr <= excelWorkBook.Sheets.Count)
excelWorkSheet = excelWorkBook.Sheets.get_Item(sheetNr);
else
excelWorkSheet = excelWorkBook.Sheets.Add(After: excelWorkBook.Sheets[excelWorkBook.Sheets.Count]);
excelWorkSheet.Name = table.TableName;
for (int i = 1; i < table.Columns.Count + 1; i++)
excelWorkSheet.Cells[1, i] = table.Columns[i - 1].ColumnName;
for (int j = 0; j < table.Rows.Count; j++)
for (int k = 0; k < table.Columns.Count; k++)
excelWorkSheet.Cells[j + 2, k + 1] = table.Rows[j].ItemArray[k].ToString();
sheetNr += 1;
//make first sheet active
excelApp.ActiveWorkbook.Sheets[1].Select();
excelWorkBook.SaveAs(@"c:\temp\DataSetToExcel.xlsx");
finally
excelWorkBook.Close();
excelApp.Quit();
//you should call GC here because there is memory problem with Interop
GC.Collect();
GC.WaitForPendingFinalizers();
#endregion
#region Take byte[] of the excel
byte[] result = null;
using (FileStream fs = new FileStream(@"c:\temp\DataSetToExcel.xlsx", FileMode.Open, FileAccess.Read))
BinaryReader reader = new BinaryReader(fs);
result = reader.ReadBytes((int)fs.Length);
#endregion
#region Delete the excel from the server
File.Delete(@"c:\temp\DataSetToExcel.xlsx");
#endregion
return result;
所以尝试使用社区已经建立的东西。这是如何使用Interop 的完整示例。 我个人更喜欢使用 ACE/JET 引擎，因为没有像 Interop 中那样的内存泄漏问题（因为我们在代码中调用了 GC）。使用 ACE/JET 引擎创建新表有点困难。
【讨论】：
我认为，上述问题与linq有关，linq过滤不正确。 @mybirthname【参考方案2】：我认为您在 linq 查询中的字符串比较有问题..您的电子邮件地址可能有不同的大小写，这可能会导致此问题。试试下面的代码
DataTable filteredEducation = dt1.AsEnumerable()
.Where(x => dt.AsEnumerable()
.Any(z => z.Field<string>("Email").Trim().Equals(x.Field<string>("Email").Trim(),StringComparison.CurrentCultureIgnoreCase)))
.CopyToDataTable();
DataTable filteredEmployee = dt2.AsEnumerable()
.Where(x => dt.AsEnumerable()
.Any(z => z.Field<string>("Email").Trim().Equals(x.Field<string>("Email").Trim(),StringComparison.CurrentCultureIgnoreCase)))
.CopyToDataTable();
【讨论】：
我收到错误：无法使用实例引用访问成员 'object.Equals(object, object)'；改为使用类型名称来限定它。 @病毒 我使用了 stringcomparer 而不是 stringcmparison 这就是错误。编辑它。请立即尝试【参考方案3】：我通过手动导出完成了同样的导出问题。首先，我需要正确准备响应 http 响应，而不是添加表的所有标题（带有 rowsapn 和 colspan 属性），然后填充数据：
//this fun is called after click on export button for example
public void Export(string fileName, GridView gv)
try
HttpContext.Current.Response.Clear();
HttpContext.Current.Response.AddHeader("content-disposition", string.Format("attachment; filename=0", String.Format("0.xls", fileName)));
HttpContext.Current.Response.AddHeader("Content-Transfer-Encoding", "utf-8");
HttpContext.Current.Response.Buffer = true;
HttpContext.Current.Response.ContentType = "application/vnd.ms-excel";
HttpContext.Current.Response.Write(@"<!DOCTYPE html PUBLIC ""-//W3C//DTD HTML 4.0 Transitional//EN"">");
HttpContext.Current.Response.Charset = "utf-8";//"windows-1251";//
HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("utf-8");
using (StringWriter sw = new StringWriter())
using (HtmlTextWriter htw = new HtmlTextWriter(sw))
// Create a table to contain the grid
Table table = new Table();
table.Width = Unit.Percentage(100);
// include the gridline settings
table.GridLines = gv.GridLines;
//header
TableRow r = new TableRow();
TableCell cell = new TableCell()
ColumnSpan = 18,
Text = fileName,
BackColor = Color.LightGray,
HorizontalAlign = HorizontalAlign.Center
;
cell.Font.Size = new FontUnit(14);
r.Cells.Add(cell);
table.Rows.Add(r);
GridViewRow row;
int rowSpan = 0;
//second row
row = CreateSecondHeaderRow();
table.Rows.AddAt(1, row);
//first row
row = CreateFirstHeaderRow(row, rowSpan);
table.Rows.AddAt(1, row);
// add each of the data rows to the table
for (int j = 0; j < gv.Rows.Count; j++)
//Set the default color
gv.Rows[j].BackColor = System.Drawing.Color.White;
for (int i = 0; i < gv.Rows[j].Cells.Count; i++)
gv.Rows[j].Cells[i].BackColor = System.Drawing.Color.White;
gv.Rows[j].Cells[i].Width = gv.Columns[i].ItemStyle.Width;
gv.Rows[j].Cells[i].Font.Size = gv.Columns[i].ItemStyle.Font.Size;
gv.Rows[j].Cells[i].Font.Bold = gv.Columns[i].ItemStyle.Font.Bold;
gv.Rows[j].Cells[i].Font.Italic = gv.Columns[i].ItemStyle.Font.Italic;
//aligh
if (i == 0)
gv.Rows[j].Cells[i].Style["text-align"] = "center";
else
gv.Rows[j].Cells[i].Style["text-align"] = "right";
//for alternate
if (j % 2 != 1) gv.Rows[j].Cells[i].BackColor = Color.LightSteelBlue;
table.Rows.Add(gv.Rows[j]);
table.RenderControl(htw);
// render the htmlwriter into the response
HttpContext.Current.Response.Write(sw);
HttpContext.Current.Response.Flush();
HttpContext.Current.Response.End();
catch (Exception ex)
this._hasError = true;
ShowError(ex);
private TableHeaderCell CreateHeaderCell(string text = null, int rowSpan = 0, int columnSpan = 0, Color backColor = default(Color), Color foreColor = default(Color))
if (object.Equals(backColor, default(Color))) backColor = Color.LightGray;
if (object.Equals(foreColor, default(Color))) foreColor = Color.Black;
return new TableHeaderCell
RowSpan = rowSpan,
ColumnSpan = columnSpan,
Text = text,
BackColor = backColor
;
private GridViewRow CreateFirstHeaderRow(GridViewRow row, int rowSpan)
row = new GridViewRow(0, 0, DataControlRowType.Header, DataControlRowState.Insert);
TableHeaderCell cell = CreateHeaderCell("Surplus %");
row.Controls.Add(cell);
cell = CreateHeaderCell("The date", columnSpan: 2);
row.Controls.Add(cell);
if (this.WithQuantity)
cell = CreateHeaderCell("Total Quantity", 2 + rowSpan, backColor: Color.Yellow);
row.Controls.Add(cell);
cell = CreateHeaderCell("Total Amount", 2 + rowSpan);
row.Controls.Add(cell);
cell = CreateHeaderCell("Has elapsed periods from start", columnSpan: (this.WithQuantity ? (SurplusUtil.TheColumnsNumbers * 2) : SurplusUtil.TheColumnsNumbers));
row.Controls.Add(cell);
if (this.WithQuantity)
cell = CreateHeaderCell("Quantity <br style='mso-data-placement:same-cell;' /> surplus", 2 + rowSpan, backColor: Color.Yellow);
row.Controls.Add(cell);
cell = CreateHeaderCell("Principal <br style='mso-data-placement:same-cell;' /> surplus", 2 + rowSpan);
row.Controls.Add(cell);
return row;
private GridViewRow CreateSecondHeaderRow()
GridViewRow row = new GridViewRow(0, 0, DataControlRowType.Header, DataControlRowState.Insert);
TableHeaderCell cell = CreateHeaderCell("Period number", rowSpan: ((this.WithQuantity) ? 2 : 0));
row.Controls.Add(cell);
cell = CreateHeaderCell("from", rowSpan: ((this.WithQuantity) ? 2 : 0));
row.Controls.Add(cell);
cell = CreateHeaderCell("to", rowSpan: ((this.WithQuantity) ? 2 : 0));
row.Controls.Add(cell);
for (int i = 0; i < SurplusUtil.TheColumnsNumbers; i++)
cell = CreateHeaderCell(i.ToString(),
columnSpan: ((this.WithQuantity) ? 2 : 0),
backColor: System.Drawing.Color.FromArgb(198, 239, 206),
foreColor: System.Drawing.Color.FromArgb(0, 97, 0));
row.Controls.Add(cell);
return row;
【讨论】：
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