关于c＃：如何将DataTable导出到Excel


How to export DataTable to Excel

我怎样才能将DataTable导出到excel中？我正在使用Windows窗体。DataTable与DataGridView控制有关。我必须将DataTable的记录导出到excel。

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我建议关闭DXML-

您可以使用一些非常可读的代码将数据表转换为Excel工作表：

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XLWorkbook wb = new XLWorkbook();
DataTable dt = GetDataTableOrWhatever();
wb.Worksheets.Add(dt,"WorksheetName");

开发人员具有响应性和帮助性。该项目是积极开发的，文件是一流的。

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尝试使用简单的代码，将数据表转换为Excel文件作为csv：

2

这将在"当前工作目录"中写入一个新文件excel.csv，该目录通常是.exe所在的位置或从中启动它的位置。

注意，输出将逗号(","放在数据表中已经包含的数据之间。由于它不转义数据中的逗号，因此读取文件的程序将错误解释数据中的逗号。

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一个优雅的选项是为.NET框架的DataTable类编写扩展方法(见下文)。

可按如下方式调用此扩展方法：

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using System;
using System.Collections.Generic;
using System.Linq;
using Excel = Microsoft.Office.Interop.Excel;
using System.Data;
using System.Data.OleDb;

DataTable dt;
// fill table data in dt here
...

// export DataTable to excel
// save excel file without ever making it visible if filepath is given
// don't save excel file, just make it visible if no filepath is given
dt.ExportToExcel(ExcelFilePath);

DataTable类的扩展方法：

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public static class My_DataTable_Extensions
{

    // Export DataTable into an excel file with field names in the header line
    // - Save excel file without ever making it visible if filepath is given
    // - Don't save excel file, just make it visible if no filepath is given
    public static void ExportToExcel(this DataTable tbl, string excelFilePath = null) {
        try {
            if (tbl == null || tbl.Columns.Count == 0)
                throw new Exception("ExportToExcel: Null or empty input table!
");

            // load excel, and create a new workbook
            var excelApp = new Excel.Application();
            excelApp.Workbooks.Add();

            // single worksheet
            Excel._Worksheet workSheet = excelApp.ActiveSheet;

            // column headings
            for (var i = 0; i < tbl.Columns.Count; i++) {
                workSheet.Cells[1, i + 1] = tbl.Columns[i].ColumnName;
            }

            // rows
            for (var i = 0; i < tbl.Rows.Count; i++) {
                // to do: format datetime values before printing
                for (var j = 0; j < tbl.Columns.Count; j++) {
                    workSheet.Cells[i + 2, j + 1] = tbl.Rows[i][j];
                }
            }

            // check file path
            if (!string.IsNullOrEmpty(excelFilePath)) {
                try {
                    workSheet.SaveAs(excelFilePath);
                    excelApp.Quit();
                    MessageBox.Show("Excel file saved!");
                }
                catch (Exception ex) {
                    throw new Exception("ExportToExcel: Excel file could not be saved! Check filepath.
"
                                        + ex.Message);
                }
            } else { // no file path is given
                excelApp.Visible = true;
            }
        }
        catch (Exception ex) {
            throw new Exception("ExportToExcel:
" + ex.Message);
        }
    }
}
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基于tuncalik(感谢您的想法)文章的解决方案，但在使用大表的情况下，它的工作速度要快得多(而且不太清楚)。

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public static class My_DataTable_Extensions
{
    /// <summary>
    /// Export DataTable to Excel file
    /// </summary>
    /// <param name="DataTable">Source DataTable</param>
    /// <param name="ExcelFilePath">Path to result file name</param>
    public static void ExportToExcel(this System.Data.DataTable DataTable, string ExcelFilePath = null)
    {
        try
        {
            int ColumnsCount;

            if (DataTable == null || (ColumnsCount = DataTable.Columns.Count) == 0)
                throw new Exception("ExportToExcel: Null or empty input table!
");

            // load excel, and create a new workbook
            Microsoft.Office.Interop.Excel.Application Excel = new Microsoft.Office.Interop.Excel.Application();
            Excel.Workbooks.Add();

            // single worksheet
            Microsoft.Office.Interop.Excel._Worksheet Worksheet = Excel.ActiveSheet;

            object[] Header = new object[ColumnsCount];

            // column headings              
            for (int i = 0; i < ColumnsCount; i++)
                Header[i] = DataTable.Columns[i].ColumnName;

            Microsoft.Office.Interop.Excel.Range HeaderRange = Worksheet.get_Range((Microsoft.Office.Interop.Excel.Range)(Worksheet.Cells[1, 1]), (Microsoft.Office.Interop.Excel.Range)(Worksheet.Cells[1, ColumnsCount]));
            HeaderRange.Value = Header;
            HeaderRange.Interior.Color = System.Drawing.ColorTranslator.ToOle(System.Drawing.Color.LightGray);
            HeaderRange.Font.Bold = true;

            // DataCells
            int RowsCount = DataTable.Rows.Count;
            object[,] Cells = new object[RowsCount, ColumnsCount];

            for (int j = 0; j < RowsCount; j++)
                for (int i = 0; i < ColumnsCount; i++)
                    Cells[j, i] = DataTable.Rows[j][i];

            Worksheet.get_Range((Microsoft.Office.Interop.Excel.Range)(Worksheet.Cells[2, 1]), (Microsoft.Office.Interop.Excel.Range)(Worksheet.Cells[RowsCount + 1, ColumnsCount])).Value = Cells;

            // check fielpath
            if (ExcelFilePath != null && ExcelFilePath !="")
            {
                try
                {
                    Worksheet.SaveAs(ExcelFilePath);
                    Excel.Quit();
                    System.Windows.MessageBox.Show("Excel file saved!");
                }
                catch (Exception ex)
                {
                    throw new Exception("ExportToExcel: Excel file could not be saved! Check filepath.
"
                        + ex.Message);
                }
            }
            else    // no filepath is given
            {
                Excel.Visible = true;
            }
        }
        catch (Exception ex)
        {
            throw new Exception("ExportToExcel:
" + ex.Message);
        }
    }
}
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尝试此函数传递要导出的数据表和文件路径

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public void CreateCSVFile(ref DataTable dt, string strFilePath)
{            
    try
    {
        // Create the CSV file to which grid data will be exported.
        StreamWriter sw = new StreamWriter(strFilePath, false);
        // First we will write the headers.
        //DataTable dt = m_dsProducts.Tables[0];
        int iColCount = dt.Columns.Count;
        for (int i = 0; i < iColCount; i++)
        {
            sw.Write(dt.Columns[i]);
            if (i < iColCount - 1)
            {
                sw.Write(",");
            }
        }
        sw.Write(sw.NewLine);

        // Now write all the rows.

        foreach (DataRow dr in dt.Rows)
        {
            for (int i = 0; i < iColCount; i++)
            {
                if (!Convert.IsDBNull(dr[i]))
                {
                    sw.Write(dr[i].ToString());
                }
                if (i < iColCount - 1)
                {
                    sw.Write(",");
                }
            }

            sw.Write(sw.NewLine);
        }
        sw.Close();
    }
    catch (Exception ex)
    {
        throw ex;
    }
}
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最好最简单的方法

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private void exportToExcel(DataTable dt)
    {

        /*Set up work book, work sheets, and excel application*/
        Microsoft.Office.Interop.Excel.Application oexcel = new Microsoft.Office.Interop.Excel.Application();
        try
        {
            string path = AppDomain.CurrentDomain.BaseDirectory;
            object misValue = System.Reflection.Missing.Value;
            Microsoft.Office.Interop.Excel.Workbook obook = oexcel.Workbooks.Add(misValue);
            Microsoft.Office.Interop.Excel.Worksheet osheet = new Microsoft.Office.Interop.Excel.Worksheet();


          //  obook.Worksheets.Add(misValue);

            osheet = (Microsoft.Office.Interop.Excel.Worksheet)obook.Sheets["Sheet1"];
            int colIndex = 0;
            int rowIndex = 1;

            foreach (DataColumn dc in dt.Columns)
            {
                colIndex++;
                osheet.Cells[1, colIndex] = dc.ColumnName;
            }
            foreach (DataRow dr in dt.Rows)
            {
                rowIndex++;
                colIndex = 0;

                foreach (DataColumn dc in dt.Columns)
                {
                    colIndex++;
                    osheet.Cells[rowIndex, colIndex] = dr[dc.ColumnName];
                }
            }

            osheet.Columns.AutoFit();
            string filepath ="C:\\Temp\\Book1";

            //Release and terminate excel

            obook.SaveAs(filepath);
            obook.Close();
            oexcel.Quit();
            releaseObject(osheet);

            releaseObject(obook);

            releaseObject(oexcel);
            GC.Collect();
        }
        catch (Exception ex)
        {
            oexcel.Quit();
            log.AddToErrorLog(ex, this.Name);
        }
    }
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您可以使用easyxls这个库来导出Excel文件。

检查此代码：

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DataSet ds = new DataSet();
ds.Tables.Add(dataTable);

ExcelDocument xls = new ExcelDocument();
xls.easy_WriteXLSFile_FromDataSet("datatable.xls", ds,
           new ExcelAutoFormat(Styles.AUTOFORMAT_EASYXLS1),"DataTable");

另请参阅此示例，了解如何在C_中将数据表导出到Excel。

关于tuncalik的答案，这是很好的，尤其是如果你想对代码有一点了解的话：)但是它把我的日期放在了美国格式的Excel中，即2014年3月2日在英国是2014年3月2日，而在美国是2014年2月3日，月1日，然后是一周的第二天。我需要英国格式的，有什么想法吗？

我已经检查过它在我的数据表中以英国格式存储，并且我的Excel也设置为英国，但出于某种原因，当它生成Excel文档时，它认为它是美国的(这是因为Microsoft是美国公司：)

我将尝试用文化代码进行试验，但还不确定该把它放在哪里。试过了，但没有效果。

附笔

我确实需要更改一行代码才能使其正常工作，方法是添加一个"cast"，如下所示

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// single worksheet
Excel._Worksheet workSheet = (Excel._Worksheet)excelApp.ActiveSheet;

更新：我已经通过转换为longdatetime格式实现了日期的英国格式，不过这只是一个解决方案。

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DateTime startDate = Convert.ToDateTime(myList[0].ToString());
string strStartDate = startDate.ToLongDateString();
DateTime endDate = Convert.ToDateTime(myList[myListTotalRows].ToString());
string strEndDate = endDate.ToLongDateString();

干杯。

Excel互操作：

0

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public bool DataTableToExcelFile(DataTable dt, string targetFile)
{
    const bool dontSave = false;
    bool success = true;

    //Exit if there is no rows to export
    if (dt.Rows.Count == 0) return false;

    object misValue = System.Reflection.Missing.Value;
    List<int> dateColIndex = new List<int>();
    Excel.Application excelApp = new Excel.Application();
    Excel.Workbook excelWorkBook = excelApp.Workbooks.Add(misValue);
    Excel.Worksheet excelWorkSheet = excelWorkBook.Sheets("sheet1");

    //Iterate through the DataTable and populate the Excel work sheet
    try {
        for (int i = -1; i <= dt.Rows.Count - 1; i++) {
            for (int j = 0; j <= dt.Columns.Count - 1; j++) {
                if (i < 0) {
                    //Take special care with Date columns
                    if (dt.Columns(j).DataType is typeof(DateTime)) {
                        excelWorkSheet.Cells(1, j + 1).EntireColumn.NumberFormat ="d-MMM-yyyy;@";
                        dateColIndex.Add(j);
                    }
                    //else if ... Feel free to add more Formats

                    else {
                        //Otherwise Format the column as text
                        excelWorkSheet.Cells(1, j + 1).EntireColumn.NumberFormat ="@";
                    }
                    excelWorkSheet.Cells(1, j + 1) = dt.Columns(j).Caption;
                }
                else if (dateColIndex.IndexOf(j) > -1) {
                    excelWorkSheet.Cells(i + 2, j + 1) = Convert.ToDateTime(dt.Rows(i).ItemArray(j)).ToString("d-MMM-yyyy");
                }
                else {
                    excelWorkSheet.Cells(i + 2, j + 1) = dt.Rows(i).ItemArray(j).ToString();
                }
            }
        }

        //Add Autofilters to the Excel work sheet  
        excelWorkSheet.Cells.AutoFilter(1, Type.Missing, Excel.XlAutoFilterOperator.xlAnd, Type.Missing, true);
        //Autofit columns for neatness
        excelWorkSheet.Columns.AutoFit();
        if (File.Exists(exportFile)) File.Delete(exportFile);
        excelWorkSheet.SaveAs(exportFile);
    } catch {
        success = false;
    } finally {
        //Do this irrespective of whether there was an exception or not.
        excelWorkBook.Close(dontSave);
        excelApp.Quit();
        releaseObject(excelWorkSheet);
        releaseObject(excelWorkBook);
        releaseObject(excelApp);
    }
    return success;
}

If you dont care about Dates being flipped, then use see link that shows how to populate all the cells in the Excel spreadsheet in one line of code:

Excel Interop-效率和性能

CSV：

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public string DataTableToCSV(DataTable dt, bool includeHeader, string rowFilter, string sortFilter, bool useCommaDelimiter = false, bool truncateTimesFromDates = false)
{
    dt.DefaultView.RowFilter = rowFilter;
    dt.DefaultView.Sort = sortFilter;
    DataView dv = dt.DefaultView;
    string csv = DataTableToCSV(dv.ToTable, includeHeader, useCommaDelimiter, truncateTimesFromDates);
    //reset the Filtering
    dt.DefaultView.RowFilter = string.Empty;
    return csv;
}

public string DataTableToCsv(DataTable dt, bool includeHeader, bool useCommaDelimiter = false, bool truncateTimesFromDates = false)
{
    StringBuilder sb = new StringBuilder();
    string delimter = Constants.vbTab;
    if (useCommaDelimiter)
        delimter =",";

    if (includeHeader) {
        foreach (DataColumn dc in dt.Columns) {
            sb.AppendFormat("{0}" + Constants.vbTab, dc.ColumnName);
        }

        //remove the last Tab
        sb.Remove(sb.ToString.Length - 1, 1);
        sb.Append(Environment.NewLine);
    }

    foreach (DataRow dr in dt.Rows) {
        foreach (DataColumn dc in dt.Columns) {
            if (Information.IsDate(dr(dc.ColumnName).ToString()) & dr(dc.ColumnName).ToString().Contains(".") == false & truncateTimesFromDates) {
                sb.AppendFormat("{0}" + delimter, Convert.ToDateTime(dr(dc.ColumnName).ToString()).Date.ToShortDateString());
            } else {
                sb.AppendFormat("{0}" + delimter, CheckDBNull(dr(dc.ColumnName).ToString().Replace(",","")));
            }
        }
        //remove the last Tab
        sb.Remove(sb.ToString.Length - 1, 1);
        sb.Append(Environment.NewLine);
    }
    return sb.ToString;
}

public enum enumObjectType
{
    StrType = 0,
    IntType = 1,
    DblType = 2
}

public object CheckDBNull(object obj, enumObjectType ObjectType = enumObjectType.StrType)
{
    object objReturn = null;
    objReturn = obj;
    if (ObjectType == enumObjectType.StrType & Information.IsDBNull(obj)) {
        objReturn ="";
    } else if (ObjectType == enumObjectType.IntType & Information.IsDBNull(obj)) {
        objReturn = 0;
    } else if (ObjectType == enumObjectType.DblType & Information.IsDBNull(obj)) {
        objReturn = 0.0;
    }
    return objReturn;
}
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Private tmr As System.Windows.Forms.Timer

Private Sub TestExcel() Handles Button1.Click

    '// Initial data: SQL Server table with 6 columns and 293000 rows.


    '// Data table holding all data
    Dim dt As New DataTable("F161")

    '// Create connection
    Dim conn As New SqlConnection("Server=MYSERVER;Database=Test;Trusted_Connection=Yes;")
    Dim fAdapter As New SqlDataAdapter With
    {
        .SelectCommand = New SqlCommand($"SELECT * FROM dbo.MyTable", conn)
    }

    '// Fill DataTable
    fAdapter.Fill(dt)

    '// Create Excel application
    Dim xlApp As New Excel.Application With {.Visible = True}

    '// Temporarily disable screen updating
    xlApp.ScreenUpdating = False

    '// Create brand new workbook
    Dim xlBook As Excel.Workbook = xlApp.Workbooks.Add()
    Dim xlSheet As Excel.Worksheet = DirectCast(xlBook.Sheets(1), Excel.Worksheet)

    '// Get number of rows
    Dim rows_count = dt.Rows.Count
    '// Get number of columns
    Dim cols_count = dt.Columns.Count

    '// Here 's the core idea: after receiving data
    '// you need to create an array and transfer it to sheet.
    '// Why array?
    '// Because it's the fastest way to transfer data to Excel's sheet.
    '// So, we have two tasks:
    '// 1) Create array
    '// 2) Transfer array to sheet

    '// =========================================================
    '// TASK 1: Create array
    '// =========================================================
    '// In order to create array, we need to know that
    '// Excel's Range object expects 2-D array whose lower bounds
    '// of both dimensions start from 1.
    '// This means you can't use C# array.
    '// You need to manually create such array.
    '// Since we already calculated number of rows and columns,
    '// we can use these numbers in creating array.
    Dim arr = Array.CreateInstance(GetType(Object), {rows_count, cols_count}, {1, 1})

    '// Fill array
    For r = 0 To rows_count - 1
        For c = 0 To cols_count - 1
            arr(r + 1, c + 1) = dt.Rows(r)(c)
        Next
    Next

    '// =========================================================
    '// TASK 2: Transfer array to sheet
    '// =========================================================
    '// Now we need to transfer array to sheet.
    '// So, how transfer array to sheet fast?
    '//
    '// THE FASTEST WAY TO TRANSFER DATA TO SHEET IS TO ASSIGN ARRAY TO RANGE.
    '// We could, of course, hard-code values, but Resize property
    '// makes this work a breeze:
    xlSheet.Range("A1").Resize.Resize(rows_count, cols_count).Value = arr

    '// If we decide to dump data by iterating over array,
    '// it will take LOTS of time.
    '// For r = 1 To rows_count
    '//     For c = 1 To cols_count
    '//         xlSheet.Cells(r, c) = arr(r, c)
    '//     Next
    '// Next

    '// Here are time results:
    '// 1) Assigning array to Range: 3 seconds
    '// 2) Iterating over array: 45 minutes

    '// Turn updating on
    xlApp.ScreenUpdating = True
    xlApp = Nothing
    xlBook = Nothing
    xlSheet = Nothing

    '// Here we have another problem:
    '// creating array took lots of memory (about 150 MB).
    '// Using 'GC.Collect()', by unknown reason, doesn't help here.
    '// However, if you run GC.Collect() AFTER this procedure is finished
    '// (say, by pressing another button and calling another procedure),
    '// then the memory is cleaned up.
    '// I was wondering how to avoid creating some extra button to just release memory,
    '// so I came up with the idea to use timer to call GC.
    '// After 2 seconds GC collects all generations.
    '// Do not forget to dispose timer since we need it only once.

    tmr = New Timer()
    AddHandler tmr.Tick,
        Sub()
            GC.Collect()
            GC.WaitForPendingFinalizers()
            GC.WaitForFullGCComplete()
            tmr.Dispose()
        End Sub
    tmr.Interval = TimeSpan.FromSeconds(2).TotalMilliseconds()
    tmr.Start()

End Sub

一种方法是使用ace OLEDB提供程序(另请参见Excel的连接字符串)。当然，您必须安装并注册提供者。如果安装了Excel，您应该安装它，但是在部署应用程序时，这是必须考虑的事情。

这是从ExportHelper调用helper方法的示例：ExportHelper.CreateXlsFromDataTable(myDataTable, @"C:\tmp\export.xls");。

使用ace oledb导出到Excel文件的帮助程序：

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public class ExportHelper
{
    private const string ExcelOleDbConnectionStringTemplate ="Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties="Excel 8.0;HDR=YES";";

    /// <summary>
    /// Creates the Excel file from items in DataTable and writes them to specified output file.
    /// </summary>
    public static void CreateXlsFromDataTable(DataTable dataTable, string fullFilePath)
    {
        string createTableWithHeaderScript = GenerateCreateTableCommand(dataTable);

        using (var conn = new OleDbConnection(String.Format(ExcelOleDbConnectionStringTemplate, fullFilePath)))
        {
            if (conn.State != ConnectionState.Open)
            {
                conn.Open();
            }

            OleDbCommand cmd = new OleDbCommand(createTableWithHeaderScript, conn);
            cmd.ExecuteNonQuery();

            foreach (DataRow dataExportRow in dataTable.Rows)
            {
                AddNewRow(conn, dataExportRow);
            }
        }
    }

    private static void AddNewRow(OleDbConnection conn, DataRow dataRow)
    {
        string insertCmd = GenerateInsertRowCommand(dataRow);

        using (OleDbCommand cmd = new OleDbCommand(insertCmd, conn))
        {
            AddParametersWithValue(cmd, dataRow);
            cmd.ExecuteNonQuery();
        }
    }

    /// <summary>
    /// Generates the insert row command.
    /// </summary>
    private static string GenerateInsertRowCommand(DataRow dataRow)
    {
        var stringBuilder = new StringBuilder();
        var columns = dataRow.Table.Columns.Cast<DataColumn>().ToList();
        var columnNamesCommaSeparated = string.Join(",", columns.Select(x => x.Caption));
        var questionmarkCommaSeparated = string.Join(",", columns.Select(x =>"?"));

        stringBuilder.AppendFormat("INSERT INTO [{0}] (", dataRow.Table.TableName);
        stringBuilder.Append(columnNamesCommaSeparated);
        stringBuilder.Append(") VALUES(");
        stringBuilder.Append(questionmarkCommaSeparated);
        stringBuilder.Append(")");
        return stringBuilder.ToString();
    }

    /// <summary>
    /// Adds the parameters with value.
    /// </summary>
    private static void AddParametersWithValue(OleDbCommand cmd, DataRow dataRow)
    {
        var paramNumber = 1;

        for (int i = 0; i <= dataRow.Table.Columns.Count - 1; i++)
        {
            if (!ReferenceEquals(dataRow.Table.Columns[i].DataType, typeof(int)) && !ReferenceEquals(dataRow.Table.Columns[i].DataType, typeof(decimal)))
            {
                cmd.Parameters.AddWithValue("@p" + paramNumber, dataRow[i].ToString().Replace("'","''"));
            }
            else
            {
                object value = GetParameterValue(dataRow[i]);
                OleDbParameter parameter = cmd.Parameters.AddWithValue("@p" + paramNumber, value);
                if (value is decimal)
                {
                    parameter.OleDbType = OleDbType.Currency;
                }
            }

            paramNumber = paramNumber + 1;
        }
    }

    /// <summary>
    /// Gets the formatted value for the OleDbParameter.
    /// </summary>
    private static object GetParameterValue(object value)
    {
        if (value is string)
        {
            return value.ToString().Replace("'","''");
        }
        return value;
    }

    private static string GenerateCreateTableCommand(DataTable tableDefination)
    {
        StringBuilder stringBuilder = new StringBuilder();
        bool firstcol = true;

        stringBuilder.AppendFormat("CREATE TABLE [{0}] (", tableDefination.TableName);

        foreach (DataColumn tableColumn in tableDefination.Columns)
        {
            if (!firstcol)
            {
                stringBuilder.Append(",");
            }
            firstcol = false;

            string columnDataType ="CHAR(255)";

            switch (tableColumn.DataType.Name)
            {
                case"String":
                    columnDataType ="CHAR(255)";
                    break;
                case"Int32":
                    columnDataType ="INTEGER";
                    break;
                case"Decimal":
                    // Use currency instead of decimal because of bug described at
                    // http://social.msdn.microsoft.com/Forums/vstudio/en-US/5d6248a5-ef00-4f46-be9d-853207656bcc/localization-trouble-with-oledbparameter-and-decimal?forum=csharpgeneral
                    columnDataType ="CURRENCY";
                    break;
            }

            stringBuilder.AppendFormat("{0} {1}", tableColumn.ColumnName, columnDataType);
        }
        stringBuilder.Append(")");

        return stringBuilder.ToString();
    }
}

使用以下类

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using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using excel = Microsoft.Office.Interop.Excel;
using EL = ExcelLibrary.SpreadSheet;
using System.Drawing;
using System.Collections;
using System.Runtime.InteropServices;
using System.Windows.Forms;


namespace _basic
{
public class ExcelProcesser
{
    public void WriteToExcel(System.Data.DataTable dt)
    {
        excel.Application XlObj = new excel.Application();
        XlObj.Visible = false;
        excel._Workbook WbObj = (excel.Workbook)(XlObj.Workbooks.Add(""));
        excel._Worksheet WsObj = (excel.Worksheet)WbObj.ActiveSheet;
        object misValue = System.Reflection.Missing.Value;


        try
        {
            int row = 1; int col = 1;
            foreach (DataColumn column in dt.Columns)
            {
                //adding columns
                WsObj.Cells[row, col] = column.ColumnName;
                col++;
            }
            //reset column and row variables
            col = 1;
            row++;
            for (int i = 0; i < dt.Rows.Count; i++)
            {
                //adding data
                foreach (var cell in dt.Rows[i].ItemArray)
                {
                    WsObj.Cells[row, col] = cell;
                    col++;
                }
                col = 1;
                row++;
            }
            WbObj.SaveAs(fileFullName, excel.XlFileFormat.xlWorkbookNormal, misValue, misValue, misValue, misValue, excel.XlSaveAsAccessMode.xlExclusive, misValue, misValue, misValue, misValue, misValue);
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
        finally
        {
            WbObj.Close(true, misValue, misValue);
        }
    }
}

}

This solution is basically pushing List data to Excel, It uses DataTable to achieve this, I implemented an extension method, so basically there are two things
needed.
1. An Extension Method.

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public static class ReportHelper
{
    public static string ToExcel<T>(this IList<T> data)
    {
        PropertyDescriptorCollection properties =
            TypeDescriptor.GetProperties(typeof(T));
        DataTable table = new DataTable();
        foreach (PropertyDescriptor prop in properties)
        {
            //table.Columns.Add(prop.Name, Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType);
            if (prop.Attributes[typeof(FGMS.Entity.Extensions.ReportHeaderAttribute)] != null)
            {
                table.Columns.Add(GetColumnHeader(prop), Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType);
            }
        }

        //So it seems like when there is only one row of data the headers do not appear
        //so adding a dummy blank row which fixed the issues
        //Add a blank Row - Issue # 1471
        DataRow blankRow = table.NewRow();
        table.Rows.Add(blankRow);

        foreach (T item in data)
        {
            DataRow row = table.NewRow();
            foreach (PropertyDescriptor prop in properties)
                //row[prop.Name] = prop.GetValue(item) ?? DBNull.Value;
                if (prop.Attributes[typeof(FGMS.Entity.Extensions.ReportHeaderAttribute)] != null)
                {
                    row[GetColumnHeader(prop)] = prop.GetValue(item) ?? DBNull.Value;
                }
            table.Rows.Add(row);
        }
        table.TableName ="Results";
        var filePath = System.IO.Path.GetTempPath() +"\" + System.Guid.NewGuid().ToString() +".xls";
        table.WriteXml(filePath);

        return filePath;
    }

    private static string GetColumnHeader(PropertyDescriptor prop)
    {
        return ((FGMS.Entity.Extensions.ReportHeaderAttribute)(prop.Attributes[typeof(FGMS.Entity.Extensions.ReportHeaderAttribute)])).ReportHeaderText;
    }      
}
  • Decorate your DTO classes with the Attribute [ReportHeaderAttribute("Column Name")]
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    public class UserDTO
        {
            public int Id { get; set; }
            public int SourceId { get; set; }
            public string SourceName { get; set; }

            [ReportHeaderAttribute("User Type")]
            public string UsereType { get; set; }

            [ReportHeaderAttribute("Address")]
            public string Address{ get; set; }

            [ReportHeaderAttribute("Age")]
            public int Age{ get; set; }

            public bool IsActive { get; set; }

            [ReportHeaderAttribute("Active")]
            public string IsActiveString
            {
                get
                {
                    return IsActive ?"Yes" :"No";
                }
            }}

    所有需要在Excel中作为列的内容都必须用[ReportHeaderAttribute("Column Name")]进行修饰。

    然后简单地

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    Var userList = Service.GetUsers() //Returns List of UserDTO;
    var excelFilePath = userList.ToExcel();

    HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
                var stream = new FileStream(excelFilePath, FileMode.Open);
                result.Content = new StreamContent(stream);
                result.Content.Headers.ContentType =
                    new MediaTypeHeaderValue("application/vnd.ms-excel");
                result.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment") { FileName ="UserList.xls" };

                return result;

    要将数据导出到Excel，可以使用closedxml.report库(https://github.com/closedxml/closedxml.report)。相信我，这是一个很棒的图书馆，她很容易使用。该库不需要Excel互操作。closedxml.report基于模板生成Excel文件，您可以使用任何格式在Excel中创建该模板。例如：

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        var template = new XLTemplate(@".\Templates
    eport.xlsx"    );

        using (var db = new DbDemos())
        {
            var cust = db.customers.LoadWith(c => c.Orders).First();
            template.AddVariable(cust);
            template.Generate();
        }

        template.SaveAs(outputFile);
    0

    等级

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    private DataTable getAllList()
            {
                string constr = ConfigurationManager.ConnectionStrings["RConnection"].ConnectionString;
                using (SqlConnection con = new SqlConnection(constr))
                {
                    using (SqlCommand cmd = new SqlCommand("SELECT EmpId, gender, EmpName, pOnHold FROM Employee  WHERE EmpId= '"+ AnyVariable +"' ORDER BY EmpName"))
                    {
                        using (SqlDataAdapter da = new SqlDataAdapter())
                        {
                            DataTable dt = new DataTable();
                            cmd.CommandType = CommandType.Text;
                            cmd.Connection = con;
                            da.SelectCommand = cmd;
                            da.Fill(dt);
                            dt.Columns[0].ColumnName ="Employee Id";
                            dt.Columns[1].ColumnName ="Gender";
                            dt.Columns[2].ColumnName ="Employee Name";
                            dt.Columns[3].ColumnName ="On Hold";

                            return dt;
                        }
                    }
                }
            }

    然后是另一个获取数据集的方法

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    public DataSet getDataSetExportToExcel()
            {
                DataSet ds = new DataSet();
                DataTable dtEmp = new DataTable("CLOT List");
                dtEmp = getAllList();
                 ds.Tables.Add(dtEmp);
                 ds.Tables[0].TableName ="Employee"; //If you which to use Mutliple Tabs
                 return ds;
              }

    现在单击事件按钮

    2

    旧线程-但我想我会把我的代码扔在这里。我编写了一个小函数，在指定的路径(位置)将数据表写入新的Excel工作表。此外，还需要添加对Microsoft Excel 14.0库的引用。

    我从这个线程中提取了写任何东西到Excel-如何写一些数据到Excel文件(.xlsx)

    我用它来推断如何编写数据表

    *注意，在catch语句中，我有一个ErrorHandler静态类引用(可以忽略这些引用)。

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     using excel = Microsoft.Office.Interop.Excel;
     using System.IO;
     using System.Data;
     using System.Runtime.InteropServices;

     //class and namespace wrapper is not shown in this example

     private void WriteToExcel(System.Data.DataTable dt, string location)
        {
            //instantiate excel objects (application, workbook, worksheets)
            excel.Application XlObj = new excel.Application();
            XlObj.Visible = false;
            excel._Workbook WbObj = (excel.Workbook)(XlObj.Workbooks.Add(""));
            excel._Worksheet WsObj = (excel.Worksheet)WbObj.ActiveSheet;

            //run through datatable and assign cells to values of datatable
            try
            {
                int row = 1; int col = 1;
                foreach (DataColumn column in dt.Columns)
                {
                    //adding columns
                    WsObj.Cells[row, col] = column.ColumnName;
                    col++;
                }
                //reset column and row variables
                col = 1;
                row++;
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    //adding data
                    foreach (var cell in dt.Rows[i].ItemArray)
                    {
                        WsObj.Cells[row, col] = cell;
                        col++;
                    }
                    col = 1;
                    row++;
                }
                WbObj.SaveAs(location);
            }
            catch (COMException x)
            {                
                ErrorHandler.Handle(x);
            }
            catch (Exception ex)
            {              
                ErrorHandler.Handle(ex);
            }
            finally
            {
                WbObj.Close();                
            }
        }
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