我将Sql数据导出到Excel。我目前使用的代码是：
DataTable dt = new DataTable();
// Create sql connection string
string conString = "Data Source=DELL\\SQLSERVER1;Trusted_Connection=True;DATABASE=Zelen;CONNECTION RESET=FALSE";
SqlConnection sqlCon = new SqlConnection(conString);
sqlCon.Open();
SqlDataAdapter da = new SqlDataAdapter("select LocalSKU,ItemName, QOH,Price,Discontinued,CAST(Barcode As varchar(25)) As Barcode,Integer2,Integer3,ISNULL(SalePrice,0.0000)AS SalePrice,SaleOn,ISNULL(Price2,0.0000)AS Price2 from dbo.Inventory", sqlCon);
System.Data.DataTable dtMainSQLData = new System.Data.DataTable();
da.Fill(dtMainSQLData);
DataColumnCollection dcCollection = dtMainSQLData.Columns;
// Export Data into EXCEL Sheet
Microsoft.Office.Interop.Excel.ApplicationClass ExcelApp = new Microsoft.Office.Interop.Excel.ApplicationClass();
ExcelApp.Application.Workbooks.Add(Type.Missing);
int i = 1;
int j = 1;
int s = 1;
//header row
foreach (DataColumn col in dtMainSQLData.Columns)
{
ExcelApp.Cells[i, j] = col.ColumnName;
j++;
ExcelApp.Rows.AutoFit();
ExcelApp.Columns.AutoFit();
}
i++;
//data rows
foreach (DataRow row in dtMainSQLData.Rows)
{
for (int k = 1; k < dtMainSQLData.Columns.Count + 1; k++)
{
ExcelApp.Cells[i, k] = "'" + row[k - 1].ToString();
}
i++;
s++;
Console.Write(s);
Console.Write("\n\r");
ExcelApp.Columns.AutoFit();
ExcelApp.Rows.AutoFit();
}
var b = Environment.CurrentDirectory + @"\Sheet1.xlsx";
ExcelApp.ActiveWorkbook.SaveCopyAs(b);
ExcelApp.ActiveWorkbook.Saved = true;
ExcelApp.Quit();
Console.WriteLine(".xlsx file Exported succssessfully.");
我的sql数据库中需要70000行。我在控制台应用程序中运行此脚本。 将它导出到excel文件需要一个多小时。
如何使用它来更快地导出它？
示例将不胜感激。
答案 0 :(得分：8)
选项1：
见answer。使用名为ClosedXML的库将数据写入Excel。
选项2：
获取足够大的范围以容纳所有数据，并将值设置为等于2维范围。这非常快，没有另一个引用另一个库。我尝试了70000条记录。
// Get an excel instance
Microsoft.Office.Interop.Excel.Application excel = new Microsoft.Office.Interop.Excel.Application();
// Get a workbook
Workbook wb = excel.Workbooks.Add();
// Get a worksheet
Worksheet ws = wb.Worksheets.Add();
ws.Name = "Test Export";
// Add column names to the first row
int col = 1;
foreach (DataColumn c in table.Columns) {
ws.Cells[1, col] = c.ColumnName;
col++;
}
// Create a 2D array with the data from the table
int i = 0;
string[,] data = new string[table.Rows.Count, table.Columns.Count];
foreach (DataRow row in table.Rows) {
int j = 0;
foreach (DataColumn c in table.Columns) {
data[i,j] = row[c].ToString();
j++;
}
i++;
}
// Set the range value to the 2D array
ws.Range[ws.Cells[2, 1], ws.Cells[table.Rows.Count + 1, table.Columns.Count]].value = data;
// Auto fit columns and rows, show excel, save.. etc
excel.Columns.AutoFit();
excel.Rows.AutoFit();
excel.Visible = true;
编辑：此版本在我的机器上导出了一百万条记录，大约需要一分钟。此示例使用Excel互操作并将行分成100,000个块。
// Start a stopwatch to time the process
System.Diagnostics.Stopwatch sw = new System.Diagnostics.Stopwatch();
sw.Start();
// Check if there are rows to process
if (table != null && table.Rows.Count > 0) {
// Determine the number of chunks
int chunkSize = 100000;
double chunkCountD = (double)table.Rows.Count / (double)chunkSize;
int chunkCount = table.Rows.Count / chunkSize;
chunkCount = chunkCountD > chunkCount ? chunkCount + 1 : chunkCount;
// Instantiate excel
Microsoft.Office.Interop.Excel.Application excel = new Microsoft.Office.Interop.Excel.Application();
// Get a workbook
Workbook wb = excel.Workbooks.Add();
// Get a worksheet
Worksheet ws = wb.Worksheets.Add();
ws.Name = "Test Export";
// Add column names to excel
int col = 1;
foreach (DataColumn c in table.Columns) {
ws.Cells[1, col] = c.ColumnName;
col++;
}
// Build 2D array
int i = 0;
string[,] data = new string[table.Rows.Count, table.Columns.Count];
foreach (DataRow row in table.Rows) {
int j = 0;
foreach (DataColumn c in table.Columns) {
data[i, j] = row[c].ToString();
j++;
}
i++;
}
int processed = 0;
int data2DLength = data.GetLength(1);
for (int chunk = 1; chunk <= chunkCount; chunk++) {
if (table.Rows.Count - processed < chunkSize) chunkSize = table.Rows.Count - processed;
string[,] chunkData = new string[chunkSize, data2DLength];
int l = 0;
for (int k = processed; k < chunkSize + processed; k++) {
for (int m = 0; m < data2DLength; m++) {
chunkData[l,m] = table.Rows[k][m].ToString();
}
l++;
}
// Set the range value to the chunk 2d array
ws.Range[ws.Cells[2 + processed, 1], ws.Cells[processed + chunkSize + 1, data2DLength]].value = chunkData;
processed += chunkSize;
}
// Auto fit columns and rows, show excel, save.. etc
excel.Columns.AutoFit();
excel.Rows.AutoFit();
excel.Visible = true;
}
// Stop the stopwatch and display the seconds elapsed
sw.Stop();
MessageBox.Show(sw.Elapsed.TotalSeconds.ToString());
答案 1 :(得分：0)
如果您将数据保存为CSV格式，可以将其加载到Excel中，以下是我在“代码项目”网站http://www.codeproject.com/Tips/665519/Writing-a-DataTable-to-a-CSV-file
中修改的一些代码public class Program
{
static void Main(string[] args)
{
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
DataTable dt = new DataTable();
// Create Connection object
using (SqlConnection conn = new SqlConnection(@"<Your Connection String>"))
{
// Create Command object
conn.Open();
using (SqlCommand cmd = new SqlCommand("SELECT * FROM <Your Table>", conn))
{
using (SqlDataReader reader = cmd.ExecuteReader())
{
try
{
dt.Load(reader);
using (StreamWriter writer = new StreamWriter("C:\\Temp\\dump.csv"))
{
DataConvert.ToCSV(dt, writer, false);
}
}
catch (Exception)
{
throw;
}
}
}
}
// Stop timing
stopwatch.Stop();
// Write result
Console.WriteLine("Time elapsed: {0}",
stopwatch.Elapsed);
Console.ReadKey();
}
}
public static class DataConvert
{
public static void ToCSV(DataTable sourceTable, TextWriter writer, bool includeHeaders)
{
if (includeHeaders)
{
List<string> headerValues = new List<string>();
foreach (DataColumn column in sourceTable.Columns)
{
headerValues.Add(QuoteValue(column.ColumnName));
}
writer.WriteLine(String.Join(",", headerValues.ToArray()));
}
string[] items = null;
foreach (DataRow row in sourceTable.Rows)
{
items = row.ItemArray.Select(o => QuoteValue(o.ToString())).ToArray();
writer.WriteLine(String.Join(",", items));
}
writer.Flush();
}
private static string QuoteValue(string value)
{
return String.Concat("\"", value.Replace("\"", "\"\""), "\"");
}
}
}
在我的电脑上，这需要30秒才能处理100万条记录...
答案 2 :(得分：0)
你可以尝试这个功能：
在数据表中设置数据后。
Public Shared Sub ExportDataSetToExcel(ByVal ds As DataTable, ByVal filename As String)
Dim response As HttpResponse = HttpContext.Current.Response
response.Clear()
response.Buffer = True
response.Charset = ""
response.ContentType = "application/vnd.ms-excel"
Using sw As New StringWriter()
Using htw As New HtmlTextWriter(sw)
Dim dg As New DataGrid()
dg.DataSource = ds
dg.DataBind()
dg.RenderControl(htw)
response.Charset = "UTF-8"
response.ContentEncoding = System.Text.Encoding.UTF8
response.BinaryWrite(System.Text.Encoding.UTF8.GetPreamble())
response.Output.Write(sw.ToString())
response.[End]()
End Using
End Using
End Sub
答案 3 :(得分：0)
我更喜欢Microsoft Open XML SDK的Open XML Writer。 Open XML是所有新办公文件所在的格式。
Export a large data query (60k+ rows) to Excel
Vincent Tan有一篇关于这个主题的好文章。