要将数据放入 Excel 工作表,您无需将数据放入数据集中。您可以通过多种方式将数据直接拉到 Excel 表上。其中一种方法是使用 QueryTables.Add 方法。使用这种方法,当在源上修改数据时,更改会反映在 excel 文件中。即:(使用示例罗斯文数据):
void Main()
{
Microsoft.Office.Interop.Excel.Application xl = new Microsoft.Office.Interop.Excel.Application();
var workbook = xl.Workbooks.Add();
Worksheet sht1, sht2;
sht1 = ((Worksheet)workbook.Sheets[1]);
if (workbook.Sheets.Count < 2)
{
sht2 = (Worksheet)workbook.Sheets.Add();
}
else
{
sht2 = ((Worksheet)workbook.Sheets[2]);
}
xl.Visible = true;
sht1.Move(sht2);
sht1.Name = "Data Sheet 1";
sht2.Name = "Data Sheet 2";
string strCon = @"OLEDB;Provider=SQLNCLI11.0;server=.\SQLExpress;Trusted_Connection=yes;Database=Northwind";
Range target1 = (Range)sht1.Range["A1"];
sht1.QueryTables.Add(strCon, target1, "Select * from Customers" ).Refresh();
Range target2 = (Range)sht2.Range["A1"];
sht2.QueryTables.Add(strCon, target2, "Select * from Orders").Refresh();
}
另一种选择是使用 Nuget 的 Epplus 库。使用它,您可以简单地拥有许多工作表,您可以在其中从集合中加载内容。IE:
void Main()
{
ExcelPackage pck = new ExcelPackage();
var collection1 = from c in db.Customers
select new
{
CustomerName = c.CompanyName,
ContactPerson = c.ContactName,
FirstOrder = c.Orders.Min(o => o.OrderDate),
LastOrder = c.Orders.Max(o => o.OrderDate),
OrderTotal = c.Orders.Any() ? c.Orders.Sum(o => o.OrderDetails.Sum(od => od.Quantity * od.UnitPrice)) : 0M,
Orders = c.Orders.Count()
};
var collection2 = db.Orders.Select(o => new {
OrderId = o.OrderID, Customer=o.CustomerID, OrderDate=o.OrderDate});
var ws1 = pck.Workbook.Worksheets.Add("My Sheet 1");
//Load the collection1 starting from cell A1 in ws1
ws1.Cells["A1"].LoadFromCollection(collection1, true, TableStyles.Medium9);
ws1.Cells[2, 3, collection1.Count() + 1, 3].Style.Numberformat.Format = "MMM dd, yyyy";
ws1.Cells[2, 4, collection1.Count() + 1, 4].Style.Numberformat.Format = "MMM dd, yyyy";
ws1.Cells[2, 5, collection1.Count() + 1, 5].Style.Numberformat.Format = "$#,##0.0000";
ws1.Cells[ws1.Dimension.Address].AutoFitColumns();
var ws2 = pck.Workbook.Worksheets.Add("My Sheet 2");
//Load the collection1 starting from cell A1 in ws1
ws2.Cells["A1"].LoadFromCollection(collection2, true, TableStyles.Medium9);
//...and save
var fi = new FileInfo(@"d:\temp\AnonymousCollection.xlsx");
if (fi.Exists)
{
fi.Delete();
}
pck.SaveAs(fi);
}
PS:QueryTables 和 Epplus 方法都很快。如果您无论如何都要使用数据集和/或在循环中设置单元格值,那么请确保您有小数据。